diff --git a/src/d_main.c b/src/d_main.c
index e321693ee..21f6055a2 100644
--- a/src/d_main.c
+++ b/src/d_main.c
@@ -817,7 +817,7 @@ static void IdentifyVersion(void)
 	if (srb2wad1 == NULL && srb2wad2 == NULL)
 		I_Error("No more free memory to look in %s", srb2waddir);
 	if (srb2wad1 != NULL)
-		sprintf(srb2wad1, pandf, srb2waddir, "srb2.srb");
+		sprintf(srb2wad1, pandf, srb2waddir, "srb2.pk3");
 	if (srb2wad2 != NULL)
 		sprintf(srb2wad2, pandf, srb2waddir, "srb2.wad");
 
@@ -847,9 +847,6 @@ static void IdentifyVersion(void)
 	// Add the players
 	D_AddFile(va(pandf,srb2waddir, "player.dta"));
 
-	// Add the weapons
-	D_AddFile(va(pandf,srb2waddir,"rings.dta"));
-
 #ifdef USE_PATCH_DTA
 	// Add our crappy patches to fix our bugs
 	D_AddFile(va(pandf,srb2waddir,"patch.dta"));
@@ -1137,16 +1134,15 @@ void D_SRB2Main(void)
 	//W_VerifyFileMD5(0, ASSET_HASH_SRB2_SRB); // srb2.srb/srb2.wad
 	//W_VerifyFileMD5(1, ASSET_HASH_ZONES_DTA); // zones.dta
 	//W_VerifyFileMD5(2, ASSET_HASH_PLAYER_DTA); // player.dta
-	//W_VerifyFileMD5(3, ASSET_HASH_RINGS_DTA); // rings.dta
 #ifdef USE_PATCH_DTA
-	W_VerifyFileMD5(4, ASSET_HASH_PATCH_DTA); // patch.dta
+	W_VerifyFileMD5(3, ASSET_HASH_PATCH_DTA); // patch.dta
 #endif
 
 	// don't check music.dta because people like to modify it, and it doesn't matter if they do
 	// ...except it does if they slip maps in there, and that's what W_VerifyNMUSlumps is for.
 #endif //ifndef DEVELOP
 
-	mainwads = 4; // there are 4 wads not to unload
+	mainwads = 3; // there are 3 wads not to unload
 #ifdef USE_PATCH_DTA
 	++mainwads; // patch.dta adds one more
 #endif
@@ -1373,7 +1369,9 @@ void D_SRB2Main(void)
 			else if (!dedicated && M_MapLocked(pstartmap))
 				I_Error("You need to unlock this level before you can warp to it!\n");
 			else
+			{
 				D_MapChange(pstartmap, gametype, ultimatemode, true, 0, false, false);
+			}
 		}
 	}
 	else if (M_CheckParm("-skipintro"))
diff --git a/src/d_netcmd.c b/src/d_netcmd.c
index c7d384b0d..b9c53a1b7 100644
--- a/src/d_netcmd.c
+++ b/src/d_netcmd.c
@@ -1604,16 +1604,12 @@ void D_MapChange(INT32 mapnum, INT32 newgametype, boolean pultmode, boolean rese
 {
 	static char buf[2+MAX_WADPATH+1+4];
 	static char *buf_p = buf;
-
 	// The supplied data are assumed to be good.
 	I_Assert(delay >= 0 && delay <= 2);
-
 	if (mapnum != -1)
 		CV_SetValue(&cv_nextmap, mapnum);
-
 	CONS_Debug(DBG_GAMELOGIC, "Map change: mapnum=%d gametype=%d ultmode=%d resetplayers=%d delay=%d skipprecutscene=%d\n",
 	           mapnum, newgametype, pultmode, resetplayers, delay, skipprecutscene);
-
 	if ((netgame || multiplayer) && !((gametype == newgametype) && (newgametype == GT_COOP)))
 		FLS = false;
 
@@ -1621,9 +1617,7 @@ void D_MapChange(INT32 mapnum, INT32 newgametype, boolean pultmode, boolean rese
 	{
 		UINT8 flags = 0;
 		const char *mapname = G_BuildMapName(mapnum);
-
 		I_Assert(W_CheckNumForName(mapname) != LUMPERROR);
-
 		buf_p = buf;
 		if (pultmode)
 			flags |= 1;
@@ -3243,6 +3237,8 @@ static void Command_ListWADS_f(void)
 			CONS_Printf("\x82 IWAD\x80: %s\n", tempname);
 		else if (i <= mainwads)
 			CONS_Printf("\x82 * %.2d\x80: %s\n", i, tempname);
+		else if (!wadfiles[i]->important)
+			CONS_Printf("\x86   %.2d: %s\n", i, tempname);
 		else
 			CONS_Printf("   %.2d: %s\n", i, tempname);
 	}
diff --git a/src/d_netfil.c b/src/d_netfil.c
index bf94e0ca7..72ac0dd32 100644
--- a/src/d_netfil.c
+++ b/src/d_netfil.c
@@ -753,11 +753,10 @@ void Got_Filetxpak(void)
 	char *filename = file->filename;
 	static INT32 filetime = 0;
 
-	if (!(strcmp(filename, "srb2.srb")
+	if (!(strcmp(filename, "srb2.pk3")
 		&& strcmp(filename, "srb2.wad")
 		&& strcmp(filename, "zones.dta")
 		&& strcmp(filename, "player.dta")
-		&& strcmp(filename, "rings.dta")
 		&& strcmp(filename, "patch.dta")
 		&& strcmp(filename, "music.dta")
 		))
diff --git a/src/dehacked.c b/src/dehacked.c
index 8f6dbaa1a..0e2b8b4f4 100644
--- a/src/dehacked.c
+++ b/src/dehacked.c
@@ -3346,9 +3346,15 @@ static void DEH_LoadDehackedFile(MYFILE *f)
 	if (gamestate == GS_TITLESCREEN)
 	{
 		if (introchanged)
+		{
+			menuactive = false;
 			COM_BufAddText("playintro");
+		}
 		else if (titlechanged)
+		{
+			menuactive = false;
 			COM_BufAddText("exitgame"); // Command_ExitGame_f() but delayed
+		}
 	}
 
 	dbg_line = -1;
diff --git a/src/filesrch.c b/src/filesrch.c
index b4a995154..2b5493642 100644
--- a/src/filesrch.c
+++ b/src/filesrch.c
@@ -441,7 +441,7 @@ filestatus_t filesearch(char *filename, const char *startpath, const UINT8 *want
 
 char exttable[NUM_EXT_TABLE][5] = {
 	".txt", ".cfg", // exec
-	".wad", ".soc", ".lua"}; // addfile
+	".wad", ".pk3", ".soc", ".lua"}; // addfile
 
 char filenamebuf[MAX_WADFILES][MAX_WADPATH];
 
diff --git a/src/filesrch.h b/src/filesrch.h
index c2201b453..e88242698 100644
--- a/src/filesrch.h
+++ b/src/filesrch.h
@@ -54,6 +54,7 @@ typedef enum
 	EXT_CFG,
 	EXT_LOADSTART,
 	EXT_WAD = EXT_LOADSTART,
+	EXT_PK3,
 	EXT_SOC,
 	EXT_LUA, // allowed even if not HAVE_BLUA so that we can yell on load attempt
 	NUM_EXT,
diff --git a/src/m_menu.c b/src/m_menu.c
index aa199f289..34f623718 100644
--- a/src/m_menu.c
+++ b/src/m_menu.c
@@ -4740,6 +4740,7 @@ static void M_Addons(INT32 choice)
 	addonsp[EXT_TXT] = W_CachePatchName("M_FTXT", PU_STATIC);
 	addonsp[EXT_CFG] = W_CachePatchName("M_FCFG", PU_STATIC);
 	addonsp[EXT_WAD] = W_CachePatchName("M_FWAD", PU_STATIC);
+	addonsp[EXT_PK3] = W_CachePatchName("M_FPK3", PU_STATIC);
 	addonsp[EXT_SOC] = W_CachePatchName("M_FSOC", PU_STATIC);
 	addonsp[EXT_LUA] = W_CachePatchName("M_FLUA", PU_STATIC);
 	addonsp[NUM_EXT] = W_CachePatchName("M_FUNKN", PU_STATIC);
@@ -5155,6 +5156,7 @@ static void M_HandleAddons(INT32 choice)
 						// else intentional fallthrough
 						case EXT_SOC:
 						case EXT_WAD:
+						case EXT_PK3:
 							COM_BufAddText(va("addfile %s%s", menupath, dirmenu[dir_on[menudepthleft]]+DIR_STRING));
 							addonsresponselimit = 5;
 							break;
diff --git a/src/p_setup.c b/src/p_setup.c
index 83c9348c9..26234bccb 100644
--- a/src/p_setup.c
+++ b/src/p_setup.c
@@ -354,16 +354,13 @@ UINT32 P_GetScoreForGrade(INT16 map, UINT8 mare, UINT8 grade)
   * \param lump VERTEXES lump number.
   * \sa ML_VERTEXES
   */
-static inline void P_LoadVertexes(lumpnum_t lumpnum)
+
+static inline void P_LoadRawVertexes(UINT8 *data, size_t i)
 {
-	UINT8 *data;
-	size_t i;
 	mapvertex_t *ml;
 	vertex_t *li;
 
-	// Determine number of lumps:
-	//  total lump length / vertex record length.
-	numvertexes = W_LumpLength(lumpnum) / sizeof (mapvertex_t);
+	numvertexes = i / sizeof (mapvertex_t);
 
 	if (numvertexes <= 0)
 		I_Error("Level has no vertices"); // instead of crashing
@@ -371,9 +368,6 @@ static inline void P_LoadVertexes(lumpnum_t lumpnum)
 	// Allocate zone memory for buffer.
 	vertexes = Z_Calloc(numvertexes * sizeof (*vertexes), PU_LEVEL, NULL);
 
-	// Load data into cache.
-	data = W_CacheLumpNum(lumpnum, PU_STATIC);
-
 	ml = (mapvertex_t *)data;
 	li = vertexes;
 
@@ -383,11 +377,16 @@ static inline void P_LoadVertexes(lumpnum_t lumpnum)
 		li->x = SHORT(ml->x)<<FRACBITS;
 		li->y = SHORT(ml->y)<<FRACBITS;
 	}
+}
 
-	// Free buffer memory.
+static inline void P_LoadVertexes(lumpnum_t lumpnum)
+{
+	UINT8 *data = W_CacheLumpNum(lumpnum, PU_STATIC);
+	P_LoadRawVertexes(data, W_LumpLength(lumpnum));
 	Z_Free(data);
 }
 
+
 //
 // Computes the line length in fracunits, the OpenGL render needs this
 //
@@ -427,20 +426,17 @@ static inline float P_SegLengthf(seg_t *seg)
   * \param lump Lump number of the SEGS resource.
   * \sa ::ML_SEGS
   */
-static void P_LoadSegs(lumpnum_t lumpnum)
+static void P_LoadRawSegs(UINT8 *data, size_t i)
 {
-	UINT8 *data;
-	size_t i;
 	INT32 linedef, side;
 	mapseg_t *ml;
 	seg_t *li;
 	line_t *ldef;
 
-	numsegs = W_LumpLength(lumpnum) / sizeof (mapseg_t);
+	numsegs = i / sizeof (mapseg_t);
 	if (numsegs <= 0)
 		I_Error("Level has no segs"); // instead of crashing
 	segs = Z_Calloc(numsegs * sizeof (*segs), PU_LEVEL, NULL);
-	data = W_CacheLumpNum(lumpnum, PU_STATIC);
 
 	ml = (mapseg_t *)data;
 	li = segs;
@@ -476,27 +472,30 @@ static void P_LoadSegs(lumpnum_t lumpnum)
 		li->numlights = 0;
 		li->rlights = NULL;
 	}
+}
 
+static void P_LoadSegs(lumpnum_t lumpnum)
+{
+	UINT8 *data = W_CacheLumpNum(lumpnum, PU_STATIC);
+	P_LoadRawSegs(data, W_LumpLength(lumpnum));
 	Z_Free(data);
 }
 
+
 /** Loads the SSECTORS resource from a level.
   *
   * \param lump Lump number of the SSECTORS resource.
   * \sa ::ML_SSECTORS
   */
-static inline void P_LoadSubsectors(lumpnum_t lumpnum)
+static inline void P_LoadRawSubsectors(void *data, size_t i)
 {
-	void *data;
-	size_t i;
 	mapsubsector_t *ms;
 	subsector_t *ss;
 
-	numsubsectors = W_LumpLength(lumpnum) / sizeof (mapsubsector_t);
+	numsubsectors = i / sizeof (mapsubsector_t);
 	if (numsubsectors <= 0)
 		I_Error("Level has no subsectors (did you forget to run it through a nodesbuilder?)");
 	ss = subsectors = Z_Calloc(numsubsectors * sizeof (*subsectors), PU_LEVEL, NULL);
-	data = W_CacheLumpNum(lumpnum,PU_STATIC);
 
 	ms = (mapsubsector_t *)data;
 
@@ -510,13 +509,14 @@ static inline void P_LoadSubsectors(lumpnum_t lumpnum)
 #endif
 		ss->validcount = 0;
 	}
-
-	Z_Free(data);
 }
 
-//
-// P_LoadSectors
-//
+static void P_LoadSubsectors(lumpnum_t lumpnum)
+{
+	UINT8 *data = W_CacheLumpNum(lumpnum, PU_STATIC);
+	P_LoadRawSubsectors(data, W_LumpLength(lumpnum));
+	Z_Free(data);
+}
 
 //
 // levelflats
@@ -543,24 +543,21 @@ size_t P_PrecacheLevelFlats(void)
 	return flatmemory;
 }
 
-// help function for P_LoadSectors, find a flat in the active wad files,
+// Auxiliary function. Find a flat in the active wad files,
 // allocate an id for it, and set the levelflat (to speedup search)
-//
 INT32 P_AddLevelFlat(const char *flatname, levelflat_t *levelflat)
 {
 	size_t i;
 
-	//
-	//  first scan through the already found flats
-	//
+	// Scan through the already found flats, break if it matches.
 	for (i = 0; i < numlevelflats; i++, levelflat++)
-		if (strnicmp(levelflat->name,flatname,8)==0)
+		if (strnicmp(levelflat->name, flatname, 8) == 0)
 			break;
 
-	// that flat was already found in the level, return the id
+	// If there is no match, make room for a new flat.
 	if (i == numlevelflats)
 	{
-		// store the name
+		// Store the name.
 		strlcpy(levelflat->name, flatname, sizeof (levelflat->name));
 		strupr(levelflat->name);
 
@@ -644,29 +641,31 @@ INT32 P_CheckLevelFlat(const char *flatname)
 	return (INT32)i;
 }
 
-static void P_LoadSectors(lumpnum_t lumpnum)
+// Sets up the ingame sectors structures.
+// Lumpnum is the lumpnum of a SECTORS lump.
+static void P_LoadRawSectors(UINT8 *data, size_t i)
 {
-	UINT8 *data;
-	size_t i;
 	mapsector_t *ms;
 	sector_t *ss;
 	levelflat_t *foundflats;
 
-	numsectors = W_LumpLength(lumpnum) / sizeof (mapsector_t);
+	// We count how many sectors we got.
+	numsectors = i / sizeof (mapsector_t);
 	if (numsectors <= 0)
 		I_Error("Level has no sectors");
+
+	// Allocate as much memory as we need into the global sectors table.
 	sectors = Z_Calloc(numsectors*sizeof (*sectors), PU_LEVEL, NULL);
-	data = W_CacheLumpNum(lumpnum,PU_STATIC);
-
-	//Fab : FIXME: allocate for whatever number of flats
-	//           512 different flats per level should be plenty
 
+	// Allocate a big chunk of memory as big as our MAXLEVELFLATS limit.
+	//Fab : FIXME: allocate for whatever number of flats - 512 different flats per level should be plenty
 	foundflats = calloc(MAXLEVELFLATS, sizeof (*foundflats));
 	if (foundflats == NULL)
 		I_Error("Ran out of memory while loading sectors\n");
 
 	numlevelflats = 0;
 
+	// For each counted sector, copy the sector raw data from our cache pointer ms, to the global table pointer ss.
 	ms = (mapsector_t *)data;
 	ss = sectors;
 	for (i = 0; i < numsectors; i++, ss++, ms++)
@@ -674,9 +673,6 @@ static void P_LoadSectors(lumpnum_t lumpnum)
 		ss->floorheight = SHORT(ms->floorheight)<<FRACBITS;
 		ss->ceilingheight = SHORT(ms->ceilingheight)<<FRACBITS;
 
-		//
-		//  flats
-		//
 		ss->floorpic = P_AddLevelFlat(ms->floorpic, foundflats);
 		ss->ceilingpic = P_AddLevelFlat(ms->ceilingpic, foundflats);
 
@@ -741,8 +737,6 @@ static void P_LoadSectors(lumpnum_t lumpnum)
 #endif // ----- end special tricks -----
 	}
 
-	Z_Free(data);
-
 	// set the sky flat num
 	skyflatnum = P_AddLevelFlat(SKYFLATNAME, foundflats);
 
@@ -754,22 +748,26 @@ static void P_LoadSectors(lumpnum_t lumpnum)
 	P_SetupLevelFlatAnims();
 }
 
+static void P_LoadSectors(lumpnum_t lumpnum)
+{
+	UINT8 *data = W_CacheLumpNum(lumpnum, PU_STATIC);
+	P_LoadRawSectors(data, W_LumpLength(lumpnum));
+	Z_Free(data);
+}
+
 //
 // P_LoadNodes
 //
-static void P_LoadNodes(lumpnum_t lumpnum)
+static void P_LoadRawNodes(UINT8 *data, size_t i)
 {
-	UINT8 *data;
-	size_t i;
 	UINT8 j, k;
 	mapnode_t *mn;
 	node_t *no;
 
-	numnodes = W_LumpLength(lumpnum) / sizeof (mapnode_t);
+	numnodes = i / sizeof (mapnode_t);
 	if (numnodes <= 0)
 		I_Error("Level has no nodes");
 	nodes = Z_Calloc(numnodes * sizeof (*nodes), PU_LEVEL, NULL);
-	data = W_CacheLumpNum(lumpnum, PU_STATIC);
 
 	mn = (mapnode_t *)data;
 	no = nodes;
@@ -787,7 +785,12 @@ static void P_LoadNodes(lumpnum_t lumpnum)
 				no->bbox[j][k] = SHORT(mn->bbox[j][k])<<FRACBITS;
 		}
 	}
+}
 
+static void P_LoadNodes(lumpnum_t lumpnum)
+{
+	UINT8 *data = W_CacheLumpNum(lumpnum, PU_STATIC);
+	P_LoadRawNodes(data, W_LumpLength(lumpnum));
 	Z_Free(data);
 }
 
@@ -922,18 +925,16 @@ void P_ScanThings(INT16 mapnum, INT16 wadnum, INT16 lumpnum)
 //
 // P_LoadThings
 //
-static void P_PrepareThings(lumpnum_t lumpnum)
-{
-	size_t i;
-	mapthing_t *mt;
-	UINT8 *data, *datastart;
 
-	nummapthings = W_LumpLength(lumpnum) / (5 * sizeof (INT16));
+static void P_PrepareRawThings(UINT8 *data, size_t i)
+{
+	mapthing_t *mt;
+
+	nummapthings = i / (5 * sizeof (INT16));
 	mapthings = Z_Calloc(nummapthings * sizeof (*mapthings), PU_LEVEL, NULL);
 
 	// Spawn axis points first so they are
 	// at the front of the list for fast searching.
-	data = datastart = W_CacheLumpNum(lumpnum, PU_LEVEL);
 	mt = mapthings;
 	for (i = 0; i < nummapthings; i++, mt++)
 	{
@@ -958,8 +959,13 @@ static void P_PrepareThings(lumpnum_t lumpnum)
 				break;
 		}
 	}
-	Z_Free(datastart);
+}
 
+static void P_PrepareThings(lumpnum_t lumpnum)
+{
+	UINT8 *data = W_CacheLumpNum(lumpnum, PU_STATIC);
+	P_PrepareRawThings(data, W_LumpLength(lumpnum));
+	Z_Free(data);
 }
 
 static void P_LoadThings(void)
@@ -1159,22 +1165,16 @@ void P_WriteThings(lumpnum_t lumpnum)
 	CONS_Printf(M_GetText("newthings%d.lmp saved.\n"), gamemap);
 }
 
-//
-// P_LoadLineDefs
-//
-static void P_LoadLineDefs(lumpnum_t lumpnum)
+static void P_LoadRawLineDefs(UINT8 *data, size_t i)
 {
-	UINT8 *data;
-	size_t i;
 	maplinedef_t *mld;
 	line_t *ld;
 	vertex_t *v1, *v2;
 
-	numlines = W_LumpLength(lumpnum) / sizeof (maplinedef_t);
+	numlines = i / sizeof (maplinedef_t);
 	if (numlines <= 0)
 		I_Error("Level has no linedefs");
 	lines = Z_Calloc(numlines * sizeof (*lines), PU_LEVEL, NULL);
-	data = W_CacheLumpNum(lumpnum, PU_STATIC);
 
 	mld = (maplinedef_t *)data;
 	ld = lines;
@@ -1236,7 +1236,7 @@ static void P_LoadLineDefs(lumpnum_t lumpnum)
 				if (ld->sidenum[j] != 0xffff && ld->sidenum[j] >= (UINT16)numsides)
 				{
 					ld->sidenum[j] = 0xffff;
-					CONS_Debug(DBG_SETUP, "P_LoadLineDefs: linedef %s has out-of-range sidedef number\n", sizeu1(numlines-i-1));
+					CONS_Debug(DBG_SETUP, "P_LoadRawLineDefs: linedef %s has out-of-range sidedef number\n", sizeu1(numlines-i-1));
 				}
 			}
 		}
@@ -1251,14 +1251,14 @@ static void P_LoadLineDefs(lumpnum_t lumpnum)
 		{
 			ld->sidenum[0] = 0;  // Substitute dummy sidedef for missing right side
 			// cph - print a warning about the bug
-			CONS_Debug(DBG_SETUP, "P_LoadLineDefs: linedef %s missing first sidedef\n", sizeu1(numlines-i-1));
+			CONS_Debug(DBG_SETUP, "P_LoadRawLineDefs: linedef %s missing first sidedef\n", sizeu1(numlines-i-1));
 		}
 
 		if ((ld->sidenum[1] == 0xffff) && (ld->flags & ML_TWOSIDED))
 		{
 			ld->flags &= ~ML_TWOSIDED;  // Clear 2s flag for missing left side
 			// cph - print a warning about the bug
-			CONS_Debug(DBG_SETUP, "P_LoadLineDefs: linedef %s has two-sided flag set, but no second sidedef\n", sizeu1(numlines-i-1));
+			CONS_Debug(DBG_SETUP, "P_LoadRawLineDefs: linedef %s has two-sided flag set, but no second sidedef\n", sizeu1(numlines-i-1));
 		}
 
 		if (ld->sidenum[0] != 0xffff && ld->special)
@@ -1270,7 +1270,12 @@ static void P_LoadLineDefs(lumpnum_t lumpnum)
 		ld->polyobj = NULL;
 #endif
 	}
+}
 
+static void P_LoadLineDefs(lumpnum_t lumpnum)
+{
+	UINT8 *data = W_CacheLumpNum(lumpnum, PU_STATIC);
+	P_LoadRawLineDefs(data, W_LumpLength(lumpnum));
 	Z_Free(data);
 }
 
@@ -1372,22 +1377,24 @@ static void P_LoadLineDefs2(void)
 	}
 }
 
-//
-// P_LoadSideDefs
-//
-static inline void P_LoadSideDefs(lumpnum_t lumpnum)
+
+
+static inline void P_LoadRawSideDefs(size_t i)
 {
-	numsides = W_LumpLength(lumpnum) / sizeof (mapsidedef_t);
+	numsides = i / sizeof (mapsidedef_t);
 	if (numsides <= 0)
 		I_Error("Level has no sidedefs");
 	sides = Z_Calloc(numsides * sizeof (*sides), PU_LEVEL, NULL);
 }
 
-// Delay loading texture names until after loaded linedefs.
-
-static void P_LoadSideDefs2(lumpnum_t lumpnum)
+static inline void P_LoadSideDefs(lumpnum_t lumpnum)
+{
+	P_LoadRawSideDefs(W_LumpLength(lumpnum));
+}
+
+
+static void P_LoadRawSideDefs2(void *data)
 {
-	UINT8 *data = W_CacheLumpNum(lumpnum, PU_STATIC);
 	UINT16 i;
 	INT32 num;
 
@@ -1405,7 +1412,7 @@ static void P_LoadSideDefs2(lumpnum_t lumpnum)
 
 			if (sector_num >= numsectors)
 			{
-				CONS_Debug(DBG_SETUP, "P_LoadSideDefs2: sidedef %u has out-of-range sector num %u\n", i, sector_num);
+				CONS_Debug(DBG_SETUP, "P_LoadRawSideDefs2: sidedef %u has out-of-range sector num %u\n", i, sector_num);
 				sector_num = 0;
 			}
 			sd->sector = sec = &sectors[sector_num];
@@ -1619,11 +1626,18 @@ static void P_LoadSideDefs2(lumpnum_t lumpnum)
 				break;
 		}
 	}
-
-	Z_Free(data);
 	R_ClearTextureNumCache(true);
 }
 
+// Delay loading texture names until after loaded linedefs.
+static void P_LoadSideDefs2(lumpnum_t lumpnum)
+{
+	UINT8 *data = W_CacheLumpNum(lumpnum, PU_STATIC);
+	P_LoadRawSideDefs2(data);
+	Z_Free(data);
+}
+
+
 static boolean LineInBlock(fixed_t cx1, fixed_t cy1, fixed_t cx2, fixed_t cy2, fixed_t bx1, fixed_t by1)
 {
 	fixed_t bbox[4];
@@ -2297,6 +2311,7 @@ void P_LoadThingsOnly(void)
 				centerid = i; // save id just in case
 		}
 
+
 	for (think = thinkercap.next; think != &thinkercap; think = think->next)
 	{
 		if (think->function.acp1 != (actionf_p1)P_MobjThinker)
@@ -2313,10 +2328,10 @@ void P_LoadThingsOnly(void)
 	P_PrepareThings(lastloadedmaplumpnum + ML_THINGS);
 	P_LoadThings();
 
+
 	// restore skybox viewpoint/centerpoint if necessary, set them to defaults if we can't do that
 	skyboxmo[0] = skyboxviewpnts[(viewid >= 0) ? viewid : 0];
 	skyboxmo[1] = skyboxcenterpnts[(centerid >= 0) ? centerid : 0];
-
 	P_SpawnSecretItems(true);
 }
 
@@ -2566,6 +2581,7 @@ boolean P_SetupLevel(boolean skipprecip)
 	// use gamemap to get map number.
 	// 99% of the things already did, so.
 	// Map header should always be in place at this point
+	char *lumpfullName;
 	INT32 i, loadprecip = 1, ranspecialwipe = 0;
 	INT32 loademblems = 1;
 	INT32 fromnetsave = 0;
@@ -2728,7 +2744,12 @@ boolean P_SetupLevel(boolean skipprecip)
 	}
 
 	// internal game map
-	lastloadedmaplumpnum = W_GetNumForName(maplumpname = G_BuildMapName(gamemap));
+	maplumpname = G_BuildMapName(gamemap);
+	//lastloadedmaplumpnum = LUMPERROR;
+	lastloadedmaplumpnum = W_CheckNumForName(maplumpname);
+
+	if (lastloadedmaplumpnum == INT16_MAX)
+		I_Error("Map %s not found.\n", maplumpname);
 
 	R_ReInitColormaps(mapheaderinfo[gamemap-1]->palette);
 	CON_SetupBackColormap();
@@ -2738,42 +2759,87 @@ boolean P_SetupLevel(boolean skipprecip)
 
 	P_MakeMapMD5(lastloadedmaplumpnum, &mapmd5);
 
-	// note: most of this ordering is important
-	loadedbm = P_LoadBlockMap(lastloadedmaplumpnum + ML_BLOCKMAP);
 
-	P_LoadVertexes(lastloadedmaplumpnum + ML_VERTEXES);
-	P_LoadSectors(lastloadedmaplumpnum + ML_SECTORS);
+	// HACK ALERT: Cache the WAD, get the map data into the tables, free memory.
+	// As it is implemented right now, we're assuming an uncompressed WAD.
+	// (As in, a normal PWAD, not ZWAD or anything. The lump itself can be compressed.)
+	// We're not accounting for extra lumps and scrambled lump positions. Any additional data will cause an error.
+	lumpfullName = (wadfiles[WADFILENUM(lastloadedmaplumpnum)]->lumpinfo + LUMPNUM(lastloadedmaplumpnum))->name2;
+	if (!strnicmp(lumpfullName + strlen(lumpfullName) - 4, ".wad", 4))
+	{
+		// Remember that we're assuming that the WAD will have a specific set of lumps in a specific order.
+		UINT8 *wadData = W_CacheLumpNum(lastloadedmaplumpnum, PU_STATIC);
+		//filelump_t *fileinfo = wadData + ((wadinfo_t *)wadData)->infotableofs;
+		filelump_t *fileinfo = (filelump_t *)(wadData + ((wadinfo_t *)wadData)->infotableofs);
 
-	P_LoadSideDefs(lastloadedmaplumpnum + ML_SIDEDEFS);
+		P_LoadRawVertexes(wadData + (fileinfo + ML_VERTEXES)->filepos, (fileinfo + ML_VERTEXES)->size);
+		P_LoadRawSectors(wadData + (fileinfo + ML_SECTORS)->filepos, (fileinfo + ML_SECTORS)->size);
+		P_LoadRawSideDefs((fileinfo + ML_SIDEDEFS)->size);
+		P_LoadRawLineDefs(wadData + (fileinfo + ML_LINEDEFS)->filepos, (fileinfo + ML_LINEDEFS)->size);
+		P_LoadRawSideDefs2(wadData + (fileinfo + ML_SIDEDEFS)->filepos);
+		P_LoadRawSubsectors(wadData + (fileinfo + ML_SSECTORS)->filepos, (fileinfo + ML_SSECTORS)->size);
+		P_LoadRawNodes(wadData + (fileinfo + ML_NODES)->filepos, (fileinfo + ML_NODES)->size);
+		P_LoadRawSegs(wadData + (fileinfo + ML_SEGS)->filepos, (fileinfo + ML_SEGS)->size);
 
-	P_LoadLineDefs(lastloadedmaplumpnum + ML_LINEDEFS);
-	if (!loadedbm)
-		P_CreateBlockMap(); // Graue 02-29-2004
-	P_LoadSideDefs2(lastloadedmaplumpnum + ML_SIDEDEFS);
+		// Important: take care of the ordering of the next functions.
+		if (!loadedbm)
+			P_CreateBlockMap(); // Graue 02-29-2004
+		R_MakeColormaps();
+		P_LoadLineDefs2();
+		P_GroupLines();
+		numdmstarts = numredctfstarts = numbluectfstarts = 0;
 
-	R_MakeColormaps();
-	P_LoadLineDefs2();
-	P_LoadSubsectors(lastloadedmaplumpnum + ML_SSECTORS);
-	P_LoadNodes(lastloadedmaplumpnum + ML_NODES);
-	P_LoadSegs(lastloadedmaplumpnum + ML_SEGS);
-	P_LoadReject(lastloadedmaplumpnum + ML_REJECT);
-	P_GroupLines();
+		// reset the player starts
+		for (i = 0; i < MAXPLAYERS; i++)
+			playerstarts[i] = NULL;
 
-	numdmstarts = numredctfstarts = numbluectfstarts = 0;
+		for (i = 0; i < 2; i++)
+			skyboxmo[i] = NULL;
 
-	// reset the player starts
-	for (i = 0; i < MAXPLAYERS; i++)
-		playerstarts[i] = NULL;
+		for (i = 0; i < 16; i++)
+			skyboxviewpnts[i] = skyboxcenterpnts[i] = NULL;
 
-	for (i = 0; i < 2; i++)
-		skyboxmo[i] = NULL;
+		P_MapStart();
 
-	for (i = 0; i < 16; i++)
-		skyboxviewpnts[i] = skyboxcenterpnts[i] = NULL;
+		P_PrepareRawThings(wadData + (fileinfo + ML_THINGS)->filepos, (fileinfo + ML_THINGS)->size);
+		Z_Free(wadData);
+	}
+	else
+	{
+		// Important: take care of the ordering of the next functions.
+		loadedbm = P_LoadBlockMap(lastloadedmaplumpnum + ML_BLOCKMAP);
+		P_LoadVertexes(lastloadedmaplumpnum + ML_VERTEXES);
+		P_LoadSectors(lastloadedmaplumpnum + ML_SECTORS);
+		P_LoadSideDefs(lastloadedmaplumpnum + ML_SIDEDEFS);
+		P_LoadLineDefs(lastloadedmaplumpnum + ML_LINEDEFS);
+		P_LoadSideDefs2(lastloadedmaplumpnum + ML_SIDEDEFS);
+		P_LoadSubsectors(lastloadedmaplumpnum + ML_SSECTORS);
+		P_LoadNodes(lastloadedmaplumpnum + ML_NODES);
+		P_LoadSegs(lastloadedmaplumpnum + ML_SEGS);
+		P_LoadReject(lastloadedmaplumpnum + ML_REJECT);
 
-	P_MapStart();
+		// Important: take care of the ordering of the next functions.
+		if (!loadedbm)
+			P_CreateBlockMap(); // Graue 02-29-2004
+		R_MakeColormaps();
+		P_LoadLineDefs2();
+		P_GroupLines();
+		numdmstarts = numredctfstarts = numbluectfstarts = 0;
 
-	P_PrepareThings(lastloadedmaplumpnum + ML_THINGS);
+		// reset the player starts
+		for (i = 0; i < MAXPLAYERS; i++)
+			playerstarts[i] = NULL;
+
+		for (i = 0; i < 2; i++)
+			skyboxmo[i] = NULL;
+
+		for (i = 0; i < 16; i++)
+			skyboxviewpnts[i] = skyboxcenterpnts[i] = NULL;
+
+		P_MapStart();
+
+		P_PrepareThings(lastloadedmaplumpnum + ML_THINGS);
+	}
 
 	// init gravity, tag lists,
 	// anything that P_ResetDynamicSlopes/P_LoadThings needs to know
@@ -2784,7 +2850,6 @@ boolean P_SetupLevel(boolean skipprecip)
 #endif
 
 	P_LoadThings();
-	// skybox mobj defaults
 	skyboxmo[0] = skyboxviewpnts[0];
 	skyboxmo[1] = skyboxcenterpnts[0];
 
@@ -3078,6 +3143,50 @@ boolean P_RunSOC(const char *socfilename)
 	return true;
 }
 
+// Auxiliary function for PK3 loading - looks for sound replacements.
+// NOTE: it does not really add any new sound entry or anything.
+void P_LoadSoundsRange(UINT16 wadnum, UINT16 first, UINT16 num)
+{
+	size_t j;
+	lumpinfo_t *lumpinfo = wadfiles[wadnum]->lumpinfo + first;
+	for (; num > 0; num--, lumpinfo++)
+	{
+		// Let's check whether it's replacing an existing sound or it's a brand new one.
+		for (j = 1; j < NUMSFX; j++)
+		{
+			if (S_sfx[j].name && !strnicmp(S_sfx[j].name, lumpinfo->name + 2, 6))
+			{
+				// the sound will be reloaded when needed,
+				// since sfx->data will be NULL
+				CONS_Debug(DBG_SETUP, "Sound %.8s replaced\n", lumpinfo->name);
+
+				I_FreeSfx(&S_sfx[j]);
+			}
+		}
+	}
+}
+
+// Auxiliary function for PK3 loading - looks for music and music replacements.
+// NOTE: does nothing but print debug messages. The code is handled somewhere else.
+void P_LoadMusicsRange(UINT16 wadnum, UINT16 first, UINT16 num)
+{
+	lumpinfo_t *lumpinfo = wadfiles[wadnum]->lumpinfo + first;
+	char *name;
+	for (; num > 0; num--, lumpinfo++)
+	{
+		name = lumpinfo->name;
+		if (name[0] == 'O' && name[1] == '_')
+		{
+			CONS_Debug(DBG_SETUP, "Music %.8s replaced\n", name);
+		}
+		else if (name[0] == 'D' && name[1] == '_')
+		{
+			CONS_Debug(DBG_SETUP, "Music %.8s replaced\n", name);
+		}
+	}
+	return;
+}
+
 //
 // Add a wadfile to the active wad files,
 // replace sounds, musics, patches, textures, sprites and maps
@@ -3091,47 +3200,118 @@ boolean P_AddWadFile(const char *wadfilename, char **firstmapname)
 	lumpinfo_t *lumpinfo;
 	boolean replacedcurrentmap = false;
 
-	if ((numlumps = W_LoadWadFile(wadfilename)) == INT16_MAX)
+	// Vars to help us with the position start and amount of each resource type.
+	// Useful for PK3s since they use folders.
+	// WADs use markers for some resources, but others such as sounds are checked lump-by-lump anyway.
+//	UINT16 luaPos, luaNum = 0;
+//	UINT16 socPos, socNum = 0;
+	UINT16 sfxPos, sfxNum = 0;
+	UINT16 musPos = 0, musNum = 0;
+//	UINT16 sprPos, sprNum = 0;
+	UINT16 texPos, texNum = 0;
+//	UINT16 patPos, patNum = 0;
+//	UINT16 flaPos, flaNum = 0;
+//	UINT16 mapPos, mapNum = 0;
+
+	// Init file.
+	if ((numlumps = W_InitFile(wadfilename)) == INT16_MAX)
 	{
 		refreshdirmenu |= REFRESHDIR_NOTLOADED;
 		CONS_Printf(M_GetText("Errors occured while loading %s; not added.\n"), wadfilename);
 		return false;
 	}
-	else wadnum = (UINT16)(numwadfiles-1);
+	else
+		wadnum = (UINT16)(numwadfiles-1);
 
-	//
-	// search for sound replacements
-	//
-	lumpinfo = wadfiles[wadnum]->lumpinfo;
-	for (i = 0; i < numlumps; i++, lumpinfo++)
+	switch(wadfiles[wadnum]->type)
 	{
-		name = lumpinfo->name;
-		if (name[0] == 'D')
+	case RET_PK3:
 		{
-			if (name[1] == 'S') for (j = 1; j < NUMSFX; j++)
+			// Auxiliary function - input a folder name and gives us the resource markers positions.
+			void FindFolder(const char *folName, UINT16 *start, UINT16 *end)
 			{
-				if (S_sfx[j].name && !strnicmp(S_sfx[j].name, name + 2, 6))
+				if (!stricmp(lumpinfo->name2, folName))
 				{
-					// the sound will be reloaded when needed,
-					// since sfx->data will be NULL
-					CONS_Debug(DBG_SETUP, "Sound %.8s replaced\n", name);
+					lumpinfo++;
+					*start = ++i;
+					for (; i < numlumps; i++, lumpinfo++)
+						if (strnicmp(lumpinfo->name2, folName, strlen(folName)))
+							break;
+					lumpinfo--;
+					*end = i-- - *start;
+					return;
+				}
+				return;
+			}
 
-					I_FreeSfx(&S_sfx[j]);
+			// Look for the lumps that act as resource delimitation markers.
+			lumpinfo = wadfiles[wadnum]->lumpinfo;
+			for (i = 0; i < numlumps; i++, lumpinfo++)
+			{
+//				FindFolder("Lua/",		&luaPos, &luaNum);
+//				FindFolder("SOCs/",		&socPos, &socNum);
+				FindFolder("Sounds/",	&sfxPos, &sfxNum);
+				FindFolder("Music/",	&musPos, &musNum);
+//				FindFolder("Sprites/",	&sprPos, &sprNum);
+				FindFolder("Textures/",	&texPos, &texNum);
+//				FindFolder("Patches/",	&patPos, &patNum);
+//				FindFolder("Flats/",	&flaPos, &flaNum);
+//				FindFolder("Maps/",		&mapPos, &mapNum);
+			}
 
-					sreplaces++;
+			// Update the detected resources.
+			// Note: ALWAYS load Lua scripts first, SOCs right after, and the remaining resources afterwards.
+#ifdef HAVE_BLUA
+//			if (luaNum) // Lua scripts.
+//				P_LoadLuaScrRange(wadnum, luaPos, luaNum);
+#endif
+//			if (socNum) // SOCs.
+//				P_LoadDehackRange(wadnum, socPos, socNum);
+			if (sfxNum) // Sounds. TODO: Function currently only updates already existing sounds, the rest is handled somewhere else.
+				P_LoadSoundsRange(wadnum, sfxPos, sfxNum);
+			if (musNum) // Music. TODO: Useless function right now.
+				P_LoadMusicsRange(wadnum, musPos, musNum);
+//			if (sprNum) // Sprites.
+//				R_LoadSpritsRange(wadnum, sprPos, sprNum);
+//			if (texNum) // Textures. TODO: R_LoadTextures() does the folder positioning once again. New function maybe?
+//				R_LoadTextures();
+//			if (mapNum) // Maps. TODO: Actually implement the map WAD loading code, lulz.
+//				P_LoadWadMapRange(wadnum, mapPos, mapNum);
+		}
+		break;
+	default:
+		lumpinfo = wadfiles[wadnum]->lumpinfo;
+		for (i = 0; i < numlumps; i++, lumpinfo++)
+		{
+			name = lumpinfo->name;
+			if (name[0] == 'D')
+			{
+				if (name[1] == 'S') for (j = 1; j < NUMSFX; j++)
+				{
+					if (S_sfx[j].name && !strnicmp(S_sfx[j].name, name + 2, 6))
+					{
+						// the sound will be reloaded when needed,
+						// since sfx->data will be NULL
+						CONS_Debug(DBG_SETUP, "Sound %.8s replaced\n", name);
+
+						I_FreeSfx(&S_sfx[j]);
+
+						sreplaces++;
+					}
+				}
+				else if (name[1] == '_')
+				{
+					CONS_Debug(DBG_SETUP, "Music %.8s replaced\n", name);
+					mreplaces++;
 				}
 			}
-			else if (name[1] == '_')
+			else if (name[0] == 'O' && name[1] == '_')
 			{
 				CONS_Debug(DBG_SETUP, "Music %.8s replaced\n", name);
-				mreplaces++;
+				digmreplaces++;
 			}
 		}
-		else if (name[0] == 'O' && name[1] == '_')
-		{
-			CONS_Debug(DBG_SETUP, "Music %.8s replaced\n", name);
-			digmreplaces++;
-		}
+		break;
 	}
 	if (!devparm && sreplaces)
 		CONS_Printf(M_GetText("%s sounds replaced\n"), sizeu1(sreplaces));
@@ -3140,9 +3320,7 @@ boolean P_AddWadFile(const char *wadfilename, char **firstmapname)
 	if (!devparm && digmreplaces)
 		CONS_Printf(M_GetText("%s digital musics replaced\n"), sizeu1(digmreplaces));
 
-	//
-	// search for sprite replacements
-	//
+	// Search for sprite replacements.
 	R_AddSpriteDefs(wadnum);
 
 	// Reload it all anyway, just in case they
diff --git a/src/p_setup.h b/src/p_setup.h
index 3443ffdb7..de763bed0 100644
--- a/src/p_setup.h
+++ b/src/p_setup.h
@@ -61,6 +61,8 @@ void P_LoadThingsOnly(void);
 boolean P_SetupLevel(boolean skipprecip);
 boolean P_AddWadFile(const char *wadfilename, char **firstmapname);
 boolean P_RunSOC(const char *socfilename);
+void P_LoadSoundsRange(UINT16 wadnum, UINT16 first, UINT16 num);
+void P_LoadMusicsRange(UINT16 wadnum, UINT16 first, UINT16 num);
 void P_WriteThings(lumpnum_t lump);
 size_t P_PrecacheLevelFlats(void);
 void P_AllocMapHeader(INT16 i);
diff --git a/src/p_spec.c b/src/p_spec.c
index 03643a708..803c1ab86 100644
--- a/src/p_spec.c
+++ b/src/p_spec.c
@@ -145,22 +145,23 @@ void P_InitPicAnims(void)
 	size_t i;
 
 	I_Assert(animdefs == NULL);
-
+	
 	maxanims = 0;
 
-	if (W_CheckNumForName("ANIMDEFS") != LUMPERROR)
+	for (w = numwadfiles-1; w >= 0; w--)
 	{
-		for (w = numwadfiles-1; w >= 0; w--)
-		{
-			UINT16 animdefsLumpNum;
+		UINT16 animdefsLumpNum;
 
-			// Find ANIMDEFS lump in the WAD
-			animdefsLumpNum = W_CheckNumForNamePwad("ANIMDEFS", w, 0);
-			if (animdefsLumpNum != INT16_MAX)
-				P_ParseANIMDEFSLump(w, animdefsLumpNum);
+		// Find ANIMDEFS lump in the WAD
+		animdefsLumpNum = W_CheckNumForNamePwad("ANIMDEFS", w, 0);
+
+		while (animdefsLumpNum != INT16_MAX)
+		{
+			P_ParseANIMDEFSLump(w, animdefsLumpNum);
+			animdefsLumpNum = W_CheckNumForNamePwad("ANIMDEFS", (UINT16)w, animdefsLumpNum + 1);
 		}
 	}
-
+	
 	// Define the last one
 	animdefs[maxanims].istexture = -1;
 	strncpy(animdefs[maxanims].endname, "", 9);
diff --git a/src/r_data.c b/src/r_data.c
index c578012d1..1a6162dc2 100644
--- a/src/r_data.c
+++ b/src/r_data.c
@@ -528,8 +528,8 @@ void R_FlushTextureCache(void)
 }
 
 // Need these prototypes for later; defining them here instead of r_data.h so they're "private"
-int R_CountTexturesInTEXTURESLump(UINT16 wadNum);
-void R_ParseTEXTURESLump(UINT16 wadNum, INT32 *index);
+int R_CountTexturesInTEXTURESLump(UINT16 wadNum, UINT16 lumpNum);
+void R_ParseTEXTURESLump(UINT16 wadNum, UINT16 lumpNum, INT32 *index);
 
 //
 // R_LoadTextures
@@ -567,13 +567,22 @@ void R_LoadTextures(void)
 	// but the alternative is to spend a ton of time checking and re-checking all previous entries just to skip any potentially patched textures.
 	for (w = 0, numtextures = 0; w < numwadfiles; w++)
 	{
-		texstart = W_CheckNumForNamePwad(TX_START, (UINT16)w, 0) + 1;
-		texend = W_CheckNumForNamePwad(TX_END, (UINT16)w, 0);
-		texturesLumpPos = W_CheckNumForNamePwad("TEXTURES", (UINT16)w, 0);
-
-		if (texturesLumpPos != INT16_MAX)
+		if (wadfiles[w]->type == RET_PK3)
 		{
-			numtextures += R_CountTexturesInTEXTURESLump((UINT16)w);
+			texstart = W_CheckNumForFolderStartPK3("textures/", (UINT16)w, 0);
+			texend = W_CheckNumForFolderEndPK3("textures/", (UINT16)w, texstart);
+		}
+		else
+		{
+			texstart = W_CheckNumForNamePwad(TX_START, (UINT16)w, 0) + 1;
+			texend = W_CheckNumForNamePwad(TX_END, (UINT16)w, 0);
+		}
+
+		texturesLumpPos = W_CheckNumForNamePwad("TEXTURES", (UINT16)w, 0);
+		while (texturesLumpPos != INT16_MAX)
+		{
+			numtextures += R_CountTexturesInTEXTURESLump((UINT16)w, (UINT16)texturesLumpPos);
+			texturesLumpPos = W_CheckNumForNamePwad("TEXTURES", (UINT16)w, texturesLumpPos + 1);
 		}
 
 		// Add all the textures between TX_START and TX_END
@@ -588,7 +597,6 @@ void R_LoadTextures(void)
 			I_Error("No textures detected in any WADs!\n");
 		}
 	}
-
 	// Allocate memory and initialize to 0 for all the textures we are initialising.
 	// There are actually 5 buffers allocated in one for convenience.
 	textures = Z_Calloc((numtextures * sizeof(void *)) * 5, PU_STATIC, NULL);
@@ -610,12 +618,25 @@ void R_LoadTextures(void)
 	for (i = 0, w = 0; w < numwadfiles; w++)
 	{
 		// Get the lump numbers for the markers in the WAD, if they exist.
-		texstart = W_CheckNumForNamePwad(TX_START, (UINT16)w, 0) + 1;
-		texend = W_CheckNumForNamePwad(TX_END, (UINT16)w, 0);
-		texturesLumpPos = W_CheckNumForNamePwad("TEXTURES", (UINT16)w, 0);
-
-		if (texturesLumpPos != INT16_MAX)
-			R_ParseTEXTURESLump(w,&i);
+		if (wadfiles[w]->type == RET_PK3)
+		{
+			texstart = W_CheckNumForFolderStartPK3("textures/", (UINT16)w, 0);
+			texend = W_CheckNumForFolderEndPK3("textures/", (UINT16)w, texstart);
+			texturesLumpPos = W_CheckNumForNamePwad("TEXTURES", (UINT16)w, 0);
+			while (texturesLumpPos != INT16_MAX)
+			{
+				R_ParseTEXTURESLump(w, texturesLumpPos, &i);
+				texturesLumpPos = W_CheckNumForNamePwad("TEXTURES", (UINT16)w, texturesLumpPos + 1);
+			}
+		}
+		else
+		{
+			texstart = W_CheckNumForNamePwad(TX_START, (UINT16)w, 0) + 1;
+			texend = W_CheckNumForNamePwad(TX_END, (UINT16)w, 0);
+			texturesLumpPos = W_CheckNumForNamePwad("TEXTURES", (UINT16)w, 0);
+			if (texturesLumpPos != INT16_MAX)
+				R_ParseTEXTURESLump(w, texturesLumpPos, &i);
+		}
 
 		if (texstart == INT16_MAX || texend == INT16_MAX)
 			continue;
@@ -1013,7 +1034,7 @@ static texture_t *R_ParseTexture(boolean actuallyLoadTexture)
 }
 
 // Parses the TEXTURES lump... but just to count the number of textures.
-int R_CountTexturesInTEXTURESLump(UINT16 wadNum)
+int R_CountTexturesInTEXTURESLump(UINT16 wadNum, UINT16 lumpNum)
 {
 	char *texturesLump;
 	size_t texturesLumpLength;
@@ -1024,11 +1045,11 @@ int R_CountTexturesInTEXTURESLump(UINT16 wadNum)
 	// Since lumps AREN'T \0-terminated like I'd assumed they should be, I'll
 	// need to make a space of memory where I can ensure that it will terminate
 	// correctly. Start by loading the relevant data from the WAD.
-	texturesLump = (char *)W_CacheLumpNumPwad(wadNum,W_CheckNumForNamePwad("TEXTURES", wadNum, 0),PU_STATIC);
+	texturesLump = (char *)W_CacheLumpNumPwad(wadNum, lumpNum, PU_STATIC);
 	// If that didn't exist, we have nothing to do here.
 	if (texturesLump == NULL) return 0;
 	// If we're still here, then it DOES exist; figure out how long it is, and allot memory accordingly.
-	texturesLumpLength = W_LumpLengthPwad(wadNum,W_CheckNumForNamePwad("TEXTURES",wadNum,0));
+	texturesLumpLength = W_LumpLengthPwad(wadNum, lumpNum);
 	texturesText = (char *)Z_Malloc((texturesLumpLength+1)*sizeof(char),PU_STATIC,NULL);
 	// Now move the contents of the lump into this new location.
 	memmove(texturesText,texturesLump,texturesLumpLength);
@@ -1060,7 +1081,7 @@ int R_CountTexturesInTEXTURESLump(UINT16 wadNum)
 }
 
 // Parses the TEXTURES lump... for real, this time.
-void R_ParseTEXTURESLump(UINT16 wadNum, INT32 *texindex)
+void R_ParseTEXTURESLump(UINT16 wadNum, UINT16 lumpNum, INT32 *texindex)
 {
 	char *texturesLump;
 	size_t texturesLumpLength;
@@ -1073,11 +1094,11 @@ void R_ParseTEXTURESLump(UINT16 wadNum, INT32 *texindex)
 	// Since lumps AREN'T \0-terminated like I'd assumed they should be, I'll
 	// need to make a space of memory where I can ensure that it will terminate
 	// correctly. Start by loading the relevant data from the WAD.
-	texturesLump = (char *)W_CacheLumpNumPwad(wadNum,W_CheckNumForNamePwad("TEXTURES", wadNum, 0),PU_STATIC);
+	texturesLump = (char *)W_CacheLumpNumPwad(wadNum, lumpNum, PU_STATIC);
 	// If that didn't exist, we have nothing to do here.
 	if (texturesLump == NULL) return;
 	// If we're still here, then it DOES exist; figure out how long it is, and allot memory accordingly.
-	texturesLumpLength = W_LumpLengthPwad(wadNum,W_CheckNumForNamePwad("TEXTURES",wadNum,0));
+	texturesLumpLength = W_LumpLengthPwad(wadNum, lumpNum);
 	texturesText = (char *)Z_Malloc((texturesLumpLength+1)*sizeof(char),PU_STATIC,NULL);
 	// Now move the contents of the lump into this new location.
 	memmove(texturesText,texturesLump,texturesLumpLength);
@@ -1164,12 +1185,60 @@ static void R_InitExtraColormaps(void)
 	CONS_Printf(M_GetText("Number of Extra Colormaps: %s\n"), sizeu1(numcolormaplumps));
 }
 
-// 12/14/14 -- only take flats in F_START/F_END
+// Search for flat name through all
 lumpnum_t R_GetFlatNumForName(const char *name)
 {
-	lumpnum_t lump = W_CheckNumForNameInBlock(name, "F_START", "F_END");
-	if (lump == LUMPERROR)
-		lump = W_CheckNumForNameInBlock(name, "FF_START", "FF_END"); // deutex, some other old things
+	INT32 i;
+	lumpnum_t lump;
+	lumpnum_t start;
+	lumpnum_t end;
+
+	// Scan wad files backwards so patched flats take preference.
+	for (i = numwadfiles - 1; i >= 0; i--)
+	{
+		
+		if (wadfiles[i]->type == RET_PK3)
+		{
+			start = W_CheckNumForFolderStartPK3("Flats/", i, 0);
+			if (start == INT16_MAX)
+				continue;
+			end = W_CheckNumForFolderEndPK3("Flats/", i, start);
+			if (end == INT16_MAX)
+				continue;
+		}
+		else // WAD type? use markers.
+		{
+			// Find the ranges to work with.
+			start = W_CheckNumForNamePwad("F_START", (UINT16)i, 0);
+			if (start == INT16_MAX)
+			{
+				start = W_CheckNumForNamePwad("FF_START", (UINT16)i, 0);
+				if (start == INT16_MAX)
+					continue;
+				else
+				{
+					end = W_CheckNumForNamePwad("FF_END", (UINT16)i, start);
+					if (end == INT16_MAX)
+						continue;
+				}
+			}
+			else
+			{
+				end = W_CheckNumForNamePwad("F_END", (UINT16)i, start);
+				if (end == INT16_MAX)
+					continue;
+			}
+		}
+		// Now find lump with specified name in that range.
+		lump = W_CheckNumForNamePwad(name, (UINT16)i, start);
+		if (lump < end)
+		{
+			lump += (i<<16); // found it, in our constraints
+			break;
+		}
+		lump = LUMPERROR;
+	}
+
 	if (lump == LUMPERROR)
 	{
 		if (strcmp(name, SKYFLATNAME))
@@ -1218,7 +1287,6 @@ void R_ReInitColormaps(UINT16 num)
 {
 	char colormap[9] = "COLORMAP";
 	lumpnum_t lump;
-
 	if (num > 0 && num <= 10000)
 		snprintf(colormap, 8, "CLM%04u", num-1);
 
diff --git a/src/r_things.c b/src/r_things.c
index 9ab7b5d1e..d201786a5 100644
--- a/src/r_things.c
+++ b/src/r_things.c
@@ -379,31 +379,40 @@ void R_AddSpriteDefs(UINT16 wadnum)
 	UINT16 start, end;
 	char wadname[MAX_WADPATH];
 
-	// find the sprites section in this pwad
-	// we need at least the S_END
-	// (not really, but for speedup)
-
-	start = W_CheckNumForNamePwad("S_START", wadnum, 0);
-	if (start == INT16_MAX)
-		start = W_CheckNumForNamePwad("SS_START", wadnum, 0); //deutex compatib.
-	if (start == INT16_MAX)
-		start = 0; //let say S_START is lump 0
+	// Find the sprites section in this resource file.
+	if (wadfiles[wadnum]->type == RET_PK3)
+		start = W_CheckNumForFolderStartPK3("Sprites/", wadnum, 0);
 	else
-		start++;   // just after S_START
+	{
+		start = W_CheckNumForNamePwad("S_START", wadnum, 0);
+		if (start == INT16_MAX)
+			start = W_CheckNumForNamePwad("SS_START", wadnum, 0); //deutex compatib.
+		if (start == INT16_MAX)
+			start = 0; //let say S_START is lump 0
+		else
+			start++;   // just after S_START
+	}
 
 	// ignore skin wads (we don't want skin sprites interfering with vanilla sprites)
-	if (start == 0 && W_CheckNumForNamePwad("S_SKIN", wadnum, 0) != INT16_MAX)
+	if (start == 0 && W_CheckNumForNamePwad("S_SKIN", wadnum, 0) != UINT16_MAX)
 		return;
 
-	end = W_CheckNumForNamePwad("S_END",wadnum,start);
-	if (end == INT16_MAX)
-		end = W_CheckNumForNamePwad("SS_END",wadnum,start);     //deutex compatib.
+	if (wadfiles[wadnum]->type == RET_PK3)
+		end = W_CheckNumForFolderEndPK3("Sprites/", wadnum, start);
+	else
+	{
+		end = W_CheckNumForNamePwad("S_END",wadnum,start);
+		if (end == INT16_MAX)
+			end = W_CheckNumForNamePwad("SS_END",wadnum,start);     //deutex compatib.
+	}
+
 	if (end == INT16_MAX)
 	{
 		CONS_Debug(DBG_SETUP, "no sprites in pwad %d\n", wadnum);
 		return;
 	}
 
+
 	//
 	// scan through lumps, for each sprite, find all the sprite frames
 	//
diff --git a/src/r_things.h b/src/r_things.h
index e1a171c1f..9a9761d5b 100644
--- a/src/r_things.h
+++ b/src/r_things.h
@@ -231,7 +231,7 @@ char *GetPlayerFacePic(INT32 skinnum);
 // Future: [[ ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789abcdefghijklmnopqrstuvwxyz!@ ]]
 FUNCMATH FUNCINLINE static ATTRINLINE char R_Frame2Char(UINT8 frame)
 {
-#if 1 // 2.1 compat
+#if 0 // 2.1 compat
 	return 'A' + frame;
 #else
 	if (frame < 26) return 'A' + frame;
@@ -245,7 +245,7 @@ FUNCMATH FUNCINLINE static ATTRINLINE char R_Frame2Char(UINT8 frame)
 
 FUNCMATH FUNCINLINE static ATTRINLINE UINT8 R_Char2Frame(char cn)
 {
-#if 1 // 2.1 compat
+#if 0 // 2.1 compat
 	return cn - 'A';
 #else
 	if (cn >= 'A' && cn <= 'Z') return cn - 'A';
diff --git a/src/sdl/i_system.c b/src/sdl/i_system.c
index 3e46a9b6a..0412344e6 100644
--- a/src/sdl/i_system.c
+++ b/src/sdl/i_system.c
@@ -142,7 +142,7 @@ typedef LPVOID (WINAPI *p_MapViewOfFile) (HANDLE, DWORD, DWORD, DWORD, SIZE_T);
 
 /**	\brief WAD file to look for
 */
-#define WADKEYWORD1 "srb2.srb"
+#define WADKEYWORD1 "srb2.pk3"
 #define WADKEYWORD2 "srb2.wad"
 /**	\brief holds wad path
 */
diff --git a/src/w_wad.c b/src/w_wad.c
index 2aa0a6316..c8701f98f 100644
--- a/src/w_wad.c
+++ b/src/w_wad.c
@@ -22,6 +22,22 @@
 #include "lzf.h"
 #endif
 
+#ifndef _FILE_OFFSET_BITS
+#define _FILE_OFFSET_BITS 0
+#endif
+
+#ifndef _LARGEFILE64_SOURCE
+#define _LARGEFILE64_SOURCE
+#endif
+
+#ifndef _LFS64_LARGEFILE
+#define _LFS64_LARGEFILE
+#endif
+
+//#ifdef HAVE_ZLIB
+#include "zlib.h"
+//#endif // HAVE_ZLIB
+
 #include "doomdef.h"
 #include "doomstat.h"
 #include "doomtype.h"
@@ -65,14 +81,6 @@ int	snprintf(char *str, size_t n, const char *fmt, ...);
 #pragma pack(1)
 #endif
 
-// a raw entry of the wad directory
-typedef struct
-{
-	UINT32 filepos; // file offset of the resource
-	UINT32 size; // size of the resource
-	char name[8]; // name of the resource
-} ATTRPACK filelump_t;
-
 #if defined(_MSC_VER)
 #pragma pack()
 #endif
@@ -113,6 +121,8 @@ void W_Shutdown(void)
 		fclose(wadfiles[numwadfiles]->handle);
 		Z_Free(wadfiles[numwadfiles]->lumpinfo);
 		Z_Free(wadfiles[numwadfiles]->filename);
+		while (wadfiles[numwadfiles]->numlumps--)
+			Z_Free(wadfiles[numwadfiles]->lumpinfo[wadfiles[numwadfiles]->numlumps].name2);
 		Z_Free(wadfiles[numwadfiles]);
 	}
 }
@@ -172,6 +182,26 @@ FILE *W_OpenWadFile(const char **filename, boolean useerrors)
 	return handle;
 }
 
+// Look for all DEHACKED and Lua scripts inside a PK3 archive.
+static inline void W_LoadDehackedLumpsPK3(UINT16 wadnum)
+{
+	UINT16 posStart, posEnd;
+	posStart = W_CheckNumForFolderStartPK3("Lua/", wadnum, 0);
+	if (posStart != INT16_MAX)
+	{
+		posEnd = W_CheckNumForFolderEndPK3("Lua/", wadnum, posStart);
+		for (; posStart < posEnd; posStart++)
+			LUA_LoadLump(wadnum, posStart);
+	}
+	posStart = W_CheckNumForFolderStartPK3("SOCs/", wadnum, 0);
+	if (posStart != INT16_MAX)
+	{
+		posEnd = W_CheckNumForFolderEndPK3("SOCs/", wadnum, posStart);
+		for(; posStart < posEnd; posStart++)
+			DEH_LoadDehackedLumpPwad(wadnum, posStart);
+	}
+}
+
 // search for all DEHACKED lump in all wads and load it
 static inline void W_LoadDehackedLumps(UINT16 wadnum)
 {
@@ -284,12 +314,13 @@ static void W_InvalidateLumpnumCache(void)
 //
 // Can now load dehacked files (.soc)
 //
-UINT16 W_LoadWadFile(const char *filename)
+UINT16 W_InitFile(const char *filename)
 {
 	FILE *handle;
 	lumpinfo_t *lumpinfo;
 	wadfile_t *wadfile;
-	UINT32 numlumps;
+	enum restype type;
+	UINT16 numlumps;
 	size_t i;
 	INT32 compressed = 0;
 	size_t packetsize;
@@ -335,12 +366,32 @@ UINT16 W_LoadWadFile(const char *filename)
 		packetsizetally = packetsize;
 	}
 
+#ifndef NOMD5
+	//
+	// w-waiiiit!
+	// Let's not add a wad file if the MD5 matches
+	// an MD5 of an already added WAD file!
+	//
+	W_MakeFileMD5(filename, md5sum);
+
+	for (i = 0; i < numwadfiles; i++)
+	{
+		if (!memcmp(wadfiles[i]->md5sum, md5sum, 16))
+		{
+			CONS_Alert(CONS_ERROR, M_GetText("%s is already loaded\n"), filename);
+			return INT16_MAX;
+		}
+	}
+#endif
+
 	// detect dehacked file with the "soc" extension
 	if (!stricmp(&filename[strlen(filename) - 4], ".soc"))
 	{
 		// This code emulates a wadfile with one lump name "OBJCTCFG"
 		// at position 0 and size of the whole file.
 		// This allows soc files to be like all wads, copied by network and loaded at the console.
+		type = RET_WAD;
+
 		numlumps = 1;
 		lumpinfo = Z_Calloc(sizeof (*lumpinfo), PU_STATIC, NULL);
 		lumpinfo->position = 0;
@@ -348,6 +399,10 @@ UINT16 W_LoadWadFile(const char *filename)
 		lumpinfo->size = ftell(handle);
 		fseek(handle, 0, SEEK_SET);
 		strcpy(lumpinfo->name, "OBJCTCFG");
+		// Allocate the lump's full name.
+		lumpinfo->name2 = Z_Malloc(9 * sizeof(char), PU_STATIC, NULL);
+		strcpy(lumpinfo->name2, "OBJCTCFG");
+		lumpinfo->name2[8] = '\0';
 	}
 #ifdef HAVE_BLUA
 	// detect lua script with the "lua" extension
@@ -356,6 +411,8 @@ UINT16 W_LoadWadFile(const char *filename)
 		// This code emulates a wadfile with one lump name "LUA_INIT"
 		// at position 0 and size of the whole file.
 		// This allows soc files to be like all wads, copied by network and loaded at the console.
+		type = RET_WAD;
+
 		numlumps = 1;
 		lumpinfo = Z_Calloc(sizeof (*lumpinfo), PU_STATIC, NULL);
 		lumpinfo->position = 0;
@@ -363,15 +420,205 @@ UINT16 W_LoadWadFile(const char *filename)
 		lumpinfo->size = ftell(handle);
 		fseek(handle, 0, SEEK_SET);
 		strcpy(lumpinfo->name, "LUA_INIT");
+		// Allocate the lump's full name.
+		lumpinfo->name2 = Z_Malloc(9 * sizeof(char), PU_STATIC, NULL);
+		strcpy(lumpinfo->name2, "LUA_INIT");
+		lumpinfo->name2[8] = '\0';
 	}
 #endif
+	else if (!stricmp(&filename[strlen(filename) - 4], ".pk3"))
+	{
+		char curHeader[4];
+		unsigned long size;
+		char seekPat[] = {0x50, 0x4b, 0x01, 0x02, 0x00};
+		char endPat[] = {0x50, 0x4b, 0x05, 0x06, 0x00};
+		char *s;
+		int c;
+		UINT32 position;
+		boolean matched = false;
+		lumpinfo_t *lump_p;
+
+		type = RET_PK3;
+
+		// Obtain the file's size.
+		fseek(handle, 0, SEEK_END);
+		size = ftell(handle);
+		CONS_Debug(DBG_SETUP, "PK3 size is: %ld\n", size);
+
+		// We must look for the central directory through the file. (Thanks to JTE for this algorithm.)
+		// All of the central directory entry headers have a signature of 0x50 0x4b 0x01 0x02.
+		// The first entry found means the beginning of the central directory.
+		fseek(handle, -min(size, (22 + 65536)), SEEK_CUR);
+		s = endPat;
+		while((c = fgetc(handle)) != EOF)
+		{
+			if (*s != c && s > endPat) // No match?
+				s = endPat; // We "reset" the counter by sending the s pointer back to the start of the array.
+			if (*s == c)
+			{
+				s++;
+				if (*s == 0x00) // The array pointer has reached the key char which marks the end. It means we have matched the signature.
+				{
+					matched = true;
+					CONS_Debug(DBG_SETUP, "Found PK3 central directory at position %ld.\n", ftell(handle));
+					break;
+				}
+			}
+		}
+
+		// Error if we couldn't find the central directory at all. It likely means this is not a ZIP/PK3 file.
+		if (matched == false)
+		{
+			CONS_Alert(CONS_ERROR, "No central directory inside PK3! File may be corrupted or incomplete.\n");
+			return INT16_MAX;
+		}
+
+		fseek(handle, 4, SEEK_CUR);
+		fread(&numlumps, 1, 2, handle);
+		fseek(handle, 6, SEEK_CUR);
+		fread(&position, 1, 4, handle);
+		lump_p = lumpinfo = Z_Malloc(numlumps * sizeof (*lumpinfo), PU_STATIC, NULL);
+		fseek(handle, position, SEEK_SET);
+
+		// Since we found the central directory, now we can map our lumpinfo table.
+		// We will look for file headers inside it, until we reach the central directory end signature.
+		// We exactly know what data to expect this time, so now we don't need to do a byte-by-byte search.
+		CONS_Debug(DBG_SETUP, "Now finding central directory file headers...\n");
+		for (i = 0; i < numlumps; i++, lump_p++)
+		{
+			fread(curHeader, 1, 4, handle);
+
+			// We found a central directory entry signature?
+			if (!strncmp(curHeader, seekPat, 3))
+			{
+				// Let's fill in the fields that we actually need.
+				// (Declaring all those vars might not be the optimal way to do this, sorry.)
+				char *eName;
+				int namePos;
+				int nameEnd;
+				unsigned short int eNameLen = 8;
+				unsigned short int eXFieldLen = 0;
+				unsigned short int lNameLen = 0;
+				unsigned short int lXFieldLen = 0;
+				unsigned short int eCommentLen = 0;
+				unsigned short int eCompression = 0;
+				unsigned int eSize = 0;
+				unsigned int eCompSize = 0;
+				unsigned int eLocalHeaderOffset = 0;
+				unsigned long int rememberPos = 0;
+
+				// We get the compression type indicator value.
+				fseek(handle, 6, SEEK_CUR);
+				fread(&eCompression, 1, 2, handle);
+				// Get the size
+				fseek(handle, 8, SEEK_CUR);
+				fread(&eCompSize, 1, 4, handle);
+				fread(&eSize, 1, 4, handle);
+				// We get the variable length fields.
+				fread(&eNameLen, 1, 2, handle);
+				fread(&eXFieldLen, 1, 2, handle);
+				fread(&eCommentLen, 1, 2, handle);
+				fseek(handle, 8, SEEK_CUR);
+				fread(&eLocalHeaderOffset, 1, 4, handle); // Get the offset.
+
+				eName = malloc(sizeof(char)*(eNameLen + 1));
+				fgets(eName, eNameLen + 1, handle);
+
+				// Don't load lump if folder.
+//				if (*(eName + eNameLen - 1) == '/')
+//					continue;
+
+				// We must calculate the position for the actual data.
+				// Why not eLocalHeaderOffset + 30 + eNameLen + eXFieldLen? That's because the extra field and name lengths MAY be different in the local headers.
+				rememberPos = ftell(handle);
+				fseek(handle, eLocalHeaderOffset + 26, SEEK_SET);
+				fread(&lNameLen, 1, 2, handle);
+				fread(&lXFieldLen, 1, 2, handle);
+				lump_p->position = ftell(handle) + lNameLen + lXFieldLen;
+
+				fseek(handle, rememberPos, SEEK_SET); // Let's go back to the central dir.
+				lump_p->disksize = eCompSize;
+				lump_p->size = eSize;
+
+				// We will trim the file's full name so that only the filename is left.
+				namePos = eNameLen - 1;
+				while(namePos--)
+					if(eName[namePos] == '/')
+						break;
+				namePos++;
+				// We will remove the file extension too.
+				nameEnd = 0;
+				while(nameEnd++ < 8)
+					if(eName[namePos + nameEnd] == '.')
+						break;
+				memset(lump_p->name, '\0', 9);
+				strncpy(lump_p->name, eName + namePos, nameEnd);
+
+				lump_p->name2 = Z_Malloc((eNameLen+1)*sizeof(char), PU_STATIC, NULL);
+				strncpy(lump_p->name2, eName, eNameLen);
+				lump_p->name2[eNameLen] = '\0';
+
+				// We set the compression type from what we're supporting so far.
+				switch(eCompression)
+				{
+				case 0:
+					lump_p->compression = CM_NOCOMPRESSION;
+					break;
+				case 8:
+					lump_p->compression = CM_DEFLATE;
+					break;
+				case 14:
+					lump_p->compression = CM_LZF;
+					break;
+				default:
+					CONS_Alert(CONS_WARNING, "Lump has an unsupported compression type!\n");
+					lump_p->compression = CM_UNSUPPORTED;
+					break;
+				}
+				CONS_Debug(DBG_SETUP, "File %s, data begins at: %ld\n", eName, lump_p->position);
+				fseek(handle, eXFieldLen + eCommentLen, SEEK_CUR); // We skip to where we expect the next central directory entry or end marker to be.
+				free(eName);
+			}
+			// We found the central directory end signature?
+			else if (!strncmp(curHeader, endPat, 4))
+			{
+				CONS_Debug(DBG_SETUP, "Central directory end signature found at: %ld\n", ftell(handle));
+
+				/*// We will create a "virtual" marker lump at the very end of lumpinfo for convenience.
+				// This marker will be used by the different lump-seeking (eg. textures, sprites, etc.) in PK3-specific cases in an auxiliary way.
+				lumpinfo = (lumpinfo_t*) Z_Realloc(lumpinfo, (numlumps + 1)*sizeof(*lumpinfo), PU_STATIC, NULL);
+				strcpy(lumpinfo[numlumps].name, "PK3_ENDM\0");
+				lumpinfo[numlumps].name2 = Z_Malloc(14 * sizeof(char), PU_STATIC, NULL);
+				strcpy(lumpinfo[numlumps].name2, "PK3_ENDMARKER\0");
+				lumpinfo[numlumps].position = 0;
+				lumpinfo[numlumps].size = 0;
+				lumpinfo[numlumps].disksize = 0;
+				lumpinfo[numlumps].compression = CM_NOCOMPRESSION;
+				numlumps++;*/
+				break;
+			}
+			// ... None of them? We're only expecting either a central directory signature entry or the central directory end signature.
+			// The file may be broken or incomplete...
+			else
+			{
+				CONS_Alert(CONS_WARNING, "Expected central directory header signature, got something else!");
+				return INT16_MAX;
+			}
+		}
+		// If we've reached this far, then it means our dynamically stored lumpinfo has to be ready.
+		// Now we finally build our... incorrectly called wadfile.
+		// TODO: Maybe we should give them more generalized names, like resourcefile or resfile or something.
+		// Mostly for clarity and better understanding when reading the code.
+	}
+	// assume wad file
 	else
 	{
-		// assume wad file
 		wadinfo_t header;
 		lumpinfo_t *lump_p;
 		filelump_t *fileinfo;
 		void *fileinfov;
+		
+		type = RET_WAD;
 
 		// read the header
 		if (fread(&header, 1, sizeof header, handle) < sizeof header)
@@ -427,47 +674,37 @@ UINT16 W_LoadWadFile(const char *filename)
 				if (realsize != 0)
 				{
 					lump_p->size = realsize;
-					lump_p->compressed = 1;
+					lump_p->compression = CM_LZF;
 				}
 				else
 				{
 					lump_p->size -= 4;
-					lump_p->compressed = 0;
+					lump_p->compression = CM_NOCOMPRESSION;
 				}
 
 				lump_p->position += 4;
 				lump_p->disksize -= 4;
 			}
-			else lump_p->compressed = 0;
+			else
+			{
+				lump_p->compression = CM_NOCOMPRESSION;
+			}
 			memset(lump_p->name, 0x00, 9);
 			strncpy(lump_p->name, fileinfo->name, 8);
+			// Allocate the lump's full name.
+			lump_p->name2 = Z_Malloc(9 * sizeof(char), PU_STATIC, NULL);
+			strncpy(lump_p->name2, fileinfo->name, 8);
+			lump_p->name2[8] = '\0';
 		}
 		free(fileinfov);
 	}
 
-#ifndef NOMD5
-	//
-	// w-waiiiit!
-	// Let's not add a wad file if the MD5 matches
-	// an MD5 of an already added WAD file!
-	//
-	W_MakeFileMD5(filename, md5sum);
-
-	for (i = 0; i < numwadfiles; i++)
-	{
-		if (!memcmp(wadfiles[i]->md5sum, md5sum, 16))
-		{
-			CONS_Alert(CONS_ERROR, M_GetText("%s is already loaded\n"), filename);
-			return INT16_MAX;
-		}
-	}
-#endif
-
 	//
 	// link wad file to search files
 	//
 	wadfile = Z_Malloc(sizeof (*wadfile), PU_STATIC, NULL);
 	wadfile->filename = Z_StrDup(filename);
+	wadfile->type = type;
 	wadfile->handle = handle;
 	wadfile->numlumps = (UINT16)numlumps;
 	wadfile->lumpinfo = lumpinfo;
@@ -494,7 +731,13 @@ UINT16 W_LoadWadFile(const char *filename)
 	CONS_Printf(M_GetText("Added file %s (%u lumps)\n"), filename, numlumps);
 	wadfiles[numwadfiles] = wadfile;
 	numwadfiles++; // must come BEFORE W_LoadDehackedLumps, so any addfile called by COM_BufInsertText called by Lua doesn't overwrite what we just loaded
-	W_LoadDehackedLumps(numwadfiles-1);
+
+	// TODO: HACK ALERT - Load Lua & SOC stuff right here. I feel like this should be out of this place, but... Let's stick with this for now.
+	if (wadfile->type == RET_WAD)
+		W_LoadDehackedLumps(numwadfiles - 1);
+	else if (wadfile->type == RET_PK3)
+		W_LoadDehackedLumpsPK3(numwadfiles - 1);
+
 
 	W_InvalidateLumpnumCache();
 
@@ -523,7 +766,7 @@ INT32 W_InitMultipleFiles(char **filenames)
 	for (; *filenames; filenames++)
 	{
 		//CONS_Debug(DBG_SETUP, "Loading %s\n", *filenames);
-		rc &= (W_LoadWadFile(*filenames) != INT16_MAX) ? 1 : 0;
+		rc &= (W_InitFile(*filenames) != INT16_MAX) ? 1 : 0;
 	}
 
 	if (!numwadfiles)
@@ -591,16 +834,59 @@ UINT16 W_CheckNumForNamePwad(const char *name, UINT16 wad, UINT16 startlump)
 	{
 		lumpinfo_t *lump_p = wadfiles[wad]->lumpinfo + startlump;
 		for (i = startlump; i < wadfiles[wad]->numlumps; i++, lump_p++)
-		{
 			if (memcmp(lump_p->name,uname,8) == 0)
 				return i;
-		}
 	}
 
 	// not found.
 	return INT16_MAX;
 }
 
+// Look for the first lump from a folder.
+UINT16 W_CheckNumForFolderStartPK3(const char *name, UINT16 wad, UINT16 startlump)
+{
+	INT32 i;
+	lumpinfo_t *lump_p = wadfiles[wad]->lumpinfo + startlump;
+	for (i = startlump; i < wadfiles[wad]->numlumps; i++, lump_p++)
+	{
+		if (strnicmp(name, lump_p->name2, strlen(name)) == 0)
+			break;
+	}
+	return i;
+}
+
+// In a PK3 type of resource file, it looks for the next lumpinfo entry that doesn't share the specified pathfile.
+// Useful for finding folder ends.
+// Returns the position of the lumpinfo entry.
+UINT16 W_CheckNumForFolderEndPK3(const char *name, UINT16 wad, UINT16 startlump)
+{
+	INT32 i;
+	lumpinfo_t *lump_p = wadfiles[wad]->lumpinfo + startlump;
+	for (i = startlump; i < wadfiles[wad]->numlumps; i++, lump_p++)
+	{
+		if (strnicmp(name, lump_p->name2, strlen(name)))
+			break;
+	}
+	return i;
+}
+
+// In a PK3 type of resource file, it looks for an entry with the specified full name.
+// Returns lump position in PK3's lumpinfo, or INT16_MAX if not found.
+UINT16 W_CheckNumForFullNamePK3(const char *name, UINT16 wad, UINT16 startlump)
+{
+	INT32 i;
+	lumpinfo_t *lump_p = wadfiles[wad]->lumpinfo + startlump;
+	for (i = startlump; i < wadfiles[wad]->numlumps; i++, lump_p++)
+	{
+		if (!strnicmp(name, lump_p->name2, strlen(name)))
+		{
+			return i;
+		}
+	}
+	// Not found at all?
+	return INT16_MAX;
+}
+
 //
 // W_CheckNumForName
 // Returns LUMPERROR if name not found.
@@ -641,6 +927,37 @@ lumpnum_t W_CheckNumForName(const char *name)
 	}
 }
 
+// Look for valid map data through all added files in descendant order.
+// Get a map marker for WADs, and a standalone WAD file lump inside PK3s.
+// TODO: Make it search through cache first, maybe...?
+lumpnum_t W_CheckNumForMap(const char *name)
+{
+	UINT16 lumpNum, end;
+	UINT32 i;
+	for (i = numwadfiles - 1; i < numwadfiles; i--)
+	{
+		if (wadfiles[i]->type == RET_WAD)
+		{
+			for (lumpNum = 0; lumpNum < wadfiles[i]->numlumps; lumpNum++)
+				if (!strncmp(name, (wadfiles[i]->lumpinfo + lumpNum)->name, 8))
+					return (i<<16) + lumpNum;
+		}
+		else if (wadfiles[i]->type == RET_PK3)
+		{
+			lumpNum = W_CheckNumForFolderStartPK3("maps/", i, 0);
+			if (lumpNum != INT16_MAX)
+				end = W_CheckNumForFolderEndPK3("maps/", i, lumpNum);
+			else
+				continue;
+			// Now look for the specified map.
+			for (++lumpNum; lumpNum < end; lumpNum++)
+				if (!strnicmp(name, (wadfiles[i]->lumpinfo + lumpNum)->name, 8))
+					return (i<<16) + lumpNum;
+		}
+	}
+	return LUMPERROR;
+}
+
 //
 // W_GetNumForName
 //
@@ -671,15 +988,20 @@ lumpnum_t W_CheckNumForNameInBlock(const char *name, const char *blockstart, con
 	// scan wad files backwards so patch lump files take precedence
 	for (i = numwadfiles - 1; i >= 0; i--)
 	{
-		bsid = W_CheckNumForNamePwad(blockstart,(UINT16)i,0);
-		if (bsid == INT16_MAX)
-			continue; // block doesn't exist, keep going
-		beid = W_CheckNumForNamePwad(blockend,(UINT16)i,0);
-		// if block end doesn't exist, just search through everything
+		if (wadfiles[i]->type == RET_WAD)
+		{
+			bsid = W_CheckNumForNamePwad(blockstart, (UINT16)i, 0);
+			if (bsid == INT16_MAX)
+				continue; // Start block doesn't exist?
+			beid = W_CheckNumForNamePwad(blockend, (UINT16)i, 0);
+			if (beid == INT16_MAX)
+				continue; // End block doesn't exist?
+
+			check = W_CheckNumForNamePwad(name, (UINT16)i, bsid);
+			if (check < beid)
+				return (i<<16)+check; // found it, in our constraints
+		}
 
-		check = W_CheckNumForNamePwad(name,(UINT16)i,bsid);
-		if (check < beid)
-			return (i<<16)+check; // found it, in our constraints
 	}
 	return LUMPERROR;
 }
@@ -716,80 +1038,35 @@ size_t W_LumpLength(lumpnum_t lumpnum)
 	return W_LumpLengthPwad(WADFILENUM(lumpnum),LUMPNUM(lumpnum));
 }
 
-/** Reads bytes from the head of a lump, without doing decompression.
-  *
-  * \param wad Wad number to read from.
-  * \param lump Lump number to read from, within wad.
-  * \param dest Buffer in memory to serve as destination.
-  * \param size Number of bytes to read.
-  * \param offest Number of bytes to offset.
-  * \return Number of bytes read (should equal size).
-  * \sa W_ReadLumpHeader
-  */
-static size_t W_RawReadLumpHeader(UINT16 wad, UINT16 lump, void *dest, size_t size, size_t offset)
+/* report a zlib or i/o error */
+void zerr(int ret)
 {
-	size_t bytesread;
-	lumpinfo_t *l;
-	FILE *handle;
-
-	l = wadfiles[wad]->lumpinfo + lump;
-
-	handle = wadfiles[wad]->handle;
-
-	fseek(handle, (long)(l->position + offset), SEEK_SET);
-	bytesread = fread(dest, 1, size, handle);
-
-	return bytesread;
-}
-
-// Read a compressed lump; return it in newly Z_Malloc'd memory.
-// wad is number of wad file, lump is number of lump in wad.
-static void *W_ReadCompressedLump(UINT16 wad, UINT16 lump)
-{
-#ifdef ZWAD
-	char *compressed, *data;
-	const lumpinfo_t *l = &wadfiles[wad]->lumpinfo[lump];
-	size_t retval;
-
-	compressed = Z_Malloc(l->disksize, PU_STATIC, NULL);
-	data = Z_Malloc(l->size, PU_STATIC, NULL);
-	if (W_RawReadLumpHeader(wad, lump, compressed, l->disksize, 0)
-		< l->disksize)
-	{
-		I_Error("wad %d, lump %d: cannot read compressed data",
-			wad, lump);
-	}
-
-	retval = lzf_decompress(compressed, l->disksize, data, l->size);
-#ifndef AVOID_ERRNO
-	if (retval == 0 && errno == E2BIG)
-	{
-		I_Error("wad %d, lump %d: compressed data too big "
-			"(bigger than %s)", wad, lump, sizeu1(l->size));
-	}
-	else if (retval == 0 && errno == EINVAL)
-		I_Error("wad %d, lump %d: invalid compressed data", wad, lump);
-	else
-#endif
-	if (retval != l->size)
-	{
-		I_Error("wad %d, lump %d: decompressed to wrong number of "
-			"bytes (expected %s, got %s)", wad, lump,
-			sizeu1(l->size), sizeu2(retval));
-	}
-	Z_Free(compressed);
-	return data;
-#else
-	(void)wad;
-	(void)lump;
-	//I_Error("ZWAD files not supported on this platform.");
-	return NULL;
-#endif
+    CONS_Printf("zpipe: ");
+    switch (ret) {
+    case Z_ERRNO:
+        if (ferror(stdin))
+            CONS_Printf("error reading stdin\n");
+        if (ferror(stdout))
+            CONS_Printf("error writing stdout\n");
+        break;
+    case Z_STREAM_ERROR:
+        CONS_Printf("invalid compression level\n");
+        break;
+    case Z_DATA_ERROR:
+        CONS_Printf("invalid or incomplete deflate data\n");
+        break;
+    case Z_MEM_ERROR:
+        CONS_Printf("out of memory\n");
+        break;
+    case Z_VERSION_ERROR:
+        CONS_Printf("zlib version mismatch!\n");
+    }
 }
 
 /** Reads bytes from the head of a lump.
   * Note: If the lump is compressed, the whole thing has to be read anyway.
   *
+  * \param wad Wad number to read from.
   * \param lump Lump number to read from.
   * \param dest Buffer in memory to serve as destination.
   * \param size Number of bytes to read.
@@ -800,6 +1077,8 @@ static void *W_ReadCompressedLump(UINT16 wad, UINT16 lump)
 size_t W_ReadLumpHeaderPwad(UINT16 wad, UINT16 lump, void *dest, size_t size, size_t offset)
 {
 	size_t lumpsize;
+	lumpinfo_t *l;
+	FILE *handle;
 
 	if (!TestValidLump(wad,lump))
 		return 0;
@@ -813,17 +1092,112 @@ size_t W_ReadLumpHeaderPwad(UINT16 wad, UINT16 lump, void *dest, size_t size, si
 	if (!size || size+offset > lumpsize)
 		size = lumpsize - offset;
 
-	if (wadfiles[wad]->lumpinfo[lump].compressed)
+	// Let's get the raw lump data.
+	// We setup the desired file handle to read the lump data.
+	l = wadfiles[wad]->lumpinfo + lump;
+	handle = wadfiles[wad]->handle;
+	fseek(handle, (long)(l->position + offset), SEEK_SET);
+
+	// But let's not copy it yet. We support different compression formats on lumps, so we need to take that into account.
+	switch(wadfiles[wad]->lumpinfo[lump].compression)
 	{
-		UINT8 *data;
-		data = W_ReadCompressedLump(wad, lump);
-		if (!data) return 0;
-		M_Memcpy(dest, data+offset, size);
-		Z_Free(data);
-		return size;
+	case CM_NOCOMPRESSION:		// If it's uncompressed, we directly write the data into our destination, and return the bytes read.
+		return fread(dest, 1, size, handle);
+	case CM_LZF:		// Is it LZF compressed? Used by ZWADs.
+		{
+#ifdef ZWAD
+			char *rawData; // The lump's raw data.
+			char *decData; // Lump's decompressed real data.
+			size_t retval; // Helper var, lzf_decompress returns 0 when an error occurs.
+
+			rawData = Z_Malloc(l->disksize, PU_STATIC, NULL);
+			decData = Z_Malloc(l->size, PU_STATIC, NULL);
+
+			if (fread(rawData, 1, l->disksize, handle) < l->disksize)
+				I_Error("wad %d, lump %d: cannot read compressed data", wad, lump);
+			retval = lzf_decompress(rawData, l->disksize, decData, l->size);
+#ifndef AVOID_ERRNO
+			if (retval == 0 && errno == E2BIG) // errno is a global var set by the lzf functions when something goes wrong.
+			{
+				I_Error("wad %d, lump %d: compressed data too big (bigger than %s)", wad, lump, sizeu1(l->size));
+			}
+			else if (retval == 0 && errno == EINVAL)
+				I_Error("wad %d, lump %d: invalid compressed data", wad, lump);
+			else
+#endif
+			if (retval != l->size)
+			{
+				I_Error("wad %d, lump %d: decompressed to wrong number of bytes (expected %s, got %s)", wad, lump, sizeu1(l->size), sizeu2(retval));
+			}
+#else
+			(void)wad;
+			(void)lump;
+			//I_Error("ZWAD files not supported on this platform.");
+			return NULL;
+#endif
+			if (!decData) // Did we get no data at all?
+				return 0;
+			M_Memcpy(dest, decData + offset, size);
+			Z_Free(rawData);
+			Z_Free(decData);
+			return size;
+		}
+	case CM_DEFLATE: // Is it compressed via DEFLATE? Very common in ZIPs/PK3s, also what most doom-related editors support.
+		{
+			z_const Bytef *rawData; // The lump's raw data.
+			Bytef *decData; // Lump's decompressed real data.
+
+			int zErr; // Helper var.
+			z_stream strm;
+			unsigned long rawSize = l->disksize;
+			unsigned long decSize = l->size;
+
+			rawData = Z_Malloc(rawSize, PU_STATIC, NULL);
+			decData = Z_Malloc(decSize, PU_STATIC, NULL);
+
+			if (fread(rawData, 1, rawSize, handle) < rawSize)
+				I_Error("wad %d, lump %d: cannot read compressed data", wad, lump);
+
+			strm.zalloc = Z_NULL;
+			strm.zfree = Z_NULL;
+			strm.opaque = Z_NULL;
+
+			strm.total_in = strm.avail_in = rawSize;
+			strm.total_out = strm.avail_out = decSize;
+
+			strm.next_in = rawData;
+			strm.next_out = decData;
+
+			zErr = inflateInit2(&strm, -15);
+			if (zErr == Z_OK)
+			{
+				zErr = inflate(&strm, Z_FINISH);
+				if (zErr == Z_STREAM_END)
+				{
+					M_Memcpy(dest, decData, size);
+				}
+				else
+				{
+					size = 0;
+					zerr(zErr);
+					(void)inflateEnd(&strm);
+				}
+			}
+			else
+			{
+				CONS_Printf("whopet\n");
+				size = 0;
+				zerr(zErr);
+			}
+
+			Z_Free(rawData);
+			Z_Free(decData);
+
+			return size;
+		}
+	default:
+		I_Error("wad %d, lump %d: unsupported compression type!", wad, lump);
 	}
-	else
-		return W_RawReadLumpHeader(wad, lump, dest, size, offset);
 }
 
 size_t W_ReadLumpHeader(lumpnum_t lumpnum, void *dest, size_t size, size_t offset)
@@ -1107,12 +1481,12 @@ static int W_VerifyFile(const char *filename, lumpchecklist_t *checklist,
 	if ((handle = W_OpenWadFile(&filename, false)) == NULL)
 		return -1;
 
-	// detect dehacked file with the "soc" extension
-	if (stricmp(&filename[strlen(filename) - 4], ".soc") != 0
+	// detect wad file by the absence of the other supported extensions
+	if (stricmp(&filename[strlen(filename) - 4], ".soc")
 #ifdef HAVE_BLUA
-	&& stricmp(&filename[strlen(filename) - 4], ".lua") != 0
+	&& stricmp(&filename[strlen(filename) - 4], ".lua")
 #endif
-	)
+	&& stricmp(&filename[strlen(filename) - 4], ".pk3"))
 	{
 		// assume wad file
 		wadinfo_t header;
diff --git a/src/w_wad.h b/src/w_wad.h
index d3ce20e20..14bf4d85f 100644
--- a/src/w_wad.h
+++ b/src/w_wad.h
@@ -34,14 +34,33 @@ typedef struct
 	UINT32 infotableofs; // the 'directory' of resources
 } wadinfo_t;
 
+// a raw entry of the wad directory
+typedef struct
+{
+	UINT32 filepos; // file offset of the resource
+	UINT32 size; // size of the resource
+	char name[8]; // name of the resource
+} ATTRPACK filelump_t;
+
+// Available compression methods for lumps.
+typedef enum 
+{
+	CM_NOCOMPRESSION, 
+	CM_DEFLATE, 
+	CM_LZF, 
+	CM_UNSUPPORTED
+} compmethod;
+
 //  a memory entry of the wad directory
 typedef struct
 {
 	unsigned long position; // filelump_t filepos
 	unsigned long disksize; // filelump_t size
 	char name[9]; // filelump_t name[]
+	char *name2; // Used by PK3s. Dynamically allocated name.
 	size_t size; // real (uncompressed) size
 	INT32 compressed; // i
+	compmethod compression; // lump compression method
 } lumpinfo_t;
 
 // =========================================================================
@@ -58,9 +77,13 @@ typedef struct
 #include "m_aatree.h"
 #endif
 
+// Resource type of the WAD. Yeah, I know this sounds dumb, but I'll leave it like this until I clean up the code further.
+enum restype {RET_WAD, RET_PK3};
+
 typedef struct wadfile_s
 {
 	char *filename;
+	enum restype type;
 	lumpinfo_t *lumpinfo;
 	lumpcache_t *lumpcache;
 #ifdef HWRENDER
@@ -86,7 +109,7 @@ void W_Shutdown(void);
 // Opens a WAD file. Returns the FILE * handle for the file, or NULL if not found or could not be opened
 FILE *W_OpenWadFile(const char **filename, boolean useerrors);
 // Load and add a wadfile to the active wad files, returns numbers of lumps, INT16_MAX on error
-UINT16 W_LoadWadFile(const char *filename);
+UINT16 W_InitFile(const char *filename);
 
 // W_InitMultipleFiles returns 1 if all is okay, 0 otherwise,
 // so that it stops with a message if a file was not found, but not if all is okay.
@@ -96,6 +119,12 @@ const char *W_CheckNameForNumPwad(UINT16 wad, UINT16 lump);
 const char *W_CheckNameForNum(lumpnum_t lumpnum);
 
 UINT16 W_CheckNumForNamePwad(const char *name, UINT16 wad, UINT16 startlump); // checks only in one pwad
+
+UINT16 W_CheckNumForFullNamePK3(const char *name, UINT16 wad, UINT16 startlump);
+UINT16 W_CheckNumForFolderStartPK3(const char *name, UINT16 wad, UINT16 startlump);
+UINT16 W_CheckNumForFolderEndPK3(const char *name, UINT16 wad, UINT16 startlump);
+
+lumpnum_t W_CheckNumForMap(const char *name);
 lumpnum_t W_CheckNumForName(const char *name);
 lumpnum_t W_GetNumForName(const char *name); // like W_CheckNumForName but I_Error on LUMPERROR
 lumpnum_t W_CheckNumForNameInBlock(const char *name, const char *blockstart, const char *blockend);
@@ -104,6 +133,8 @@ UINT8 W_LumpExists(const char *name); // Lua uses this.
 size_t W_LumpLengthPwad(UINT16 wad, UINT16 lump);
 size_t W_LumpLength(lumpnum_t lumpnum);
 
+void zerr(int ret); // zlib error checking
+
 size_t W_ReadLumpHeaderPwad(UINT16 wad, UINT16 lump, void *dest, size_t size, size_t offset);
 size_t W_ReadLumpHeader(lumpnum_t lump, void *dest, size_t size, size_t offest); // read all or a part of a lump
 void W_ReadLumpPwad(UINT16 wad, UINT16 lump, void *dest);