From 19459a735b7946881000b5dbde3e9e1550b73580 Mon Sep 17 00:00:00 2001
From: Michael Day <contact@michaelcday.com>
Date: Wed, 20 Dec 2023 22:50:11 -0500
Subject: [PATCH 1/4] doom: support Sigil II loaded as pwad

---
 src/crispy.h           |  1 +
 src/doom/d_englsh.h    | 20 ++++++++++++++++++++
 src/doom/d_main.c      |  6 ++++++
 src/doom/deh_bexpars.c |  4 ++--
 src/doom/deh_bexpars.h |  2 +-
 src/doom/f_finale.c    |  2 ++
 src/doom/g_game.c      | 16 ++++++++++++++--
 src/doom/hu_stuff.c    | 11 +++++++++++
 src/doom/m_menu.c      | 25 ++++++++++++++++++++++++-
 src/doom/p_enemy.c     |  4 ++++
 src/doom/s_sound.c     |  2 +-
 src/doom/sounds.c      | 10 ++++++++++
 src/doom/sounds.h      | 10 ++++++++++
 src/doom/st_stuff.c    |  3 ++-
 src/doom/wi_stuff.c    |  6 +++++-
 15 files changed, 113 insertions(+), 9 deletions(-)

diff --git a/src/crispy.h b/src/crispy.h
index c44dbf2d32..46460fc089 100644
--- a/src/crispy.h
+++ b/src/crispy.h
@@ -97,6 +97,7 @@ typedef struct
 	boolean fliplevels;
 	boolean flipweapons;
 	boolean haved1e5;
+	boolean haved1e6;
 	boolean havee1m10;
 	boolean havemap33;
 	boolean havessg;
diff --git a/src/doom/d_englsh.h b/src/doom/d_englsh.h
index 6dd42bdf08..9ab6a7ace2 100644
--- a/src/doom/d_englsh.h
+++ b/src/doom/d_englsh.h
@@ -207,6 +207,16 @@
 #define HUSTR_E5M8	"E5M8: Halls of Perdition"
 #define HUSTR_E5M9	"E5M9: Realm of Iblis"
 
+#define HUSTR_E6M1	"E6M1: Cursed Darkness"
+#define HUSTR_E6M2	"E6M2: Violent Hatred"
+#define HUSTR_E6M3	"E6M3: Twilight Desolation"
+#define HUSTR_E6M4	"E6M4: Fragments of Sanity"
+#define HUSTR_E6M5	"E6M5: Wrathful Reckoning"
+#define HUSTR_E6M6	"E6M6: Vengeance Unleashed"
+#define HUSTR_E6M7	"E6M7: Descent Into Terror"
+#define HUSTR_E6M8	"E6M8: Abyss of Despair"
+#define HUSTR_E6M9	"E6M9: Shattered Homecoming"
+
 #define HUSTR_1	"level 1: entryway"
 #define HUSTR_2	"level 2: underhalls"
 #define HUSTR_3	"level 3: the gantlet"
@@ -511,6 +521,16 @@
 "\n"\
 "Lock and load. Rip and tear."
 
+#define E6TEXT \
+"Satan erred in casting you to Hell's\n"\
+"darker depths. His plan failed. He has\n"\
+"tried for so long to destroy you, and he\n"\
+"has lost every single time. His only\n"\
+"option is to flood Earth with demons\n"\
+"and hope you go down fighting.\n"\
+"\n"\
+"Prepare for HELLION!"
+
 // after level 6, put this:
 
 #define C1TEXT \
diff --git a/src/doom/d_main.c b/src/doom/d_main.c
index 8ec1ce1412..a08b9fc4b2 100644
--- a/src/doom/d_main.c
+++ b/src/doom/d_main.c
@@ -2132,6 +2132,12 @@ void D_DoomMain (void)
                        (W_CheckNumForName("e5m1") != -1) &&
                        (W_CheckNumForName("wilv40") != -1);
 
+    // [crispy] check for presence of a 6th episode
+    crispy->haved1e6 = (gameversion == exe_ultimate) &&
+                       (W_CheckNumForName("m_epi6") != -1) &&
+                       (W_CheckNumForName("e6m1") != -1) &&
+                       (W_CheckNumForName("wilv50") != -1);
+
     // [crispy] check for presence of E1M10
     crispy->havee1m10 = (gamemode == retail) &&
                        (W_CheckNumForName("e1m10") != -1) &&
diff --git a/src/doom/deh_bexpars.c b/src/doom/deh_bexpars.c
index f7b540130b..5e7d1ff2df 100644
--- a/src/doom/deh_bexpars.c
+++ b/src/doom/deh_bexpars.c
@@ -22,7 +22,7 @@
 #include "deh_bexpars.h"
 #include "deh_io.h"
 
-int bex_pars[6][10] = {{0}};
+int bex_pars[7][10] = {{0}};
 int bex_cpars[32] = {0};
 
 static void *DEH_BEXParsStart(deh_context_t *context, char *line)
@@ -43,7 +43,7 @@ static void DEH_BEXParsParseLine(deh_context_t *context, char *line, void *tag)
 
     if (sscanf(line, "par %32d %32d %32d", &episode, &map, &partime) == 3)
     {
-	if (episode >= 1 && episode <= 5 && map >= 1 && map <= 9)
+	if (episode >= 1 && episode <= 6 && map >= 1 && map <= 9)
 	    bex_pars[episode][map] = partime;
 	else
 	{
diff --git a/src/doom/deh_bexpars.h b/src/doom/deh_bexpars.h
index 8dac3440d4..0fee7b42bd 100644
--- a/src/doom/deh_bexpars.h
+++ b/src/doom/deh_bexpars.h
@@ -19,7 +19,7 @@
 #ifndef DEH_BEXPARS_H
 #define DEH_BEXPARS_H
 
-extern int bex_pars[6][10];
+extern int bex_pars[7][10];
 extern int bex_cpars[32];
 
 #endif /* #ifndef DEH_BEXPARS_H */
diff --git a/src/doom/f_finale.c b/src/doom/f_finale.c
index b84f03cf95..a7e0ea8964 100644
--- a/src/doom/f_finale.c
+++ b/src/doom/f_finale.c
@@ -76,6 +76,7 @@ static textscreen_t textscreens[] =
     { doom,      3, 8,  "MFLR8_4",   E3TEXT},
     { doom,      4, 8,  "MFLR8_3",   E4TEXT},
     { doom,      5, 8,  "FLOOR7_2",  E5TEXT}, // [crispy] Sigil
+    { doom,      6, 8,  "FLOOR7_2",  E6TEXT}, // [crispy] Sigil II
 
     { doom2,     1, 6,  "SLIME16",   C1TEXT},
     { doom2,     1, 11, "RROCK14",   C2TEXT},
@@ -1012,6 +1013,7 @@ static void F_ArtScreenDrawer(void)
                 break;
             // [crispy] Sigil
             case 5:
+            case 6:
                 lumpname = "SIGILEND";
                 if (W_CheckNumForName(DEH_String(lumpname)) == -1)
                 {
diff --git a/src/doom/g_game.c b/src/doom/g_game.c
index 8bc3d565fa..9fbda51a32 100644
--- a/src/doom/g_game.c
+++ b/src/doom/g_game.c
@@ -1733,7 +1733,7 @@ void G_ScreenShot (void)
 
 
 // DOOM Par Times
-static const int pars[6][10] =
+static const int pars[7][10] =
 { 
     {0}, 
     {0,30,75,120,90,165,180,180,30,165}, 
@@ -1743,6 +1743,8 @@ static const int pars[6][10] =
    ,{0,165,255,135,150,180,390,135,360,180}
     // [crispy] Episode 5 par times from Sigil v1.21
    ,{0,90,150,360,420,780,420,780,300,660}
+    // [crispy] Episode 6 par times from Sigil II v1.0
+   ,{0,480,300,240,420,510,840,960,390,450}
 }; 
 
 // DOOM II Par Times
@@ -2011,6 +2013,7 @@ void G_DoCompleted (void)
 	    switch (gameepisode) 
 	    { 
 	      case 1: 
+	      case 6:
 		wminfo.next = 3; 
 		break; 
 	      case 2: 
@@ -2072,7 +2075,9 @@ void G_DoCompleted (void)
         // [crispy] single player par times for episode 4
         (gameepisode == 4 && crispy->singleplayer) ||
         // [crispy] par times for Sigil
-        gameepisode == 5)
+        gameepisode == 5 ||
+        // [crispy] par times for Sigil II
+        gameepisode == 6)
     {
         // [crispy] support [PARS] sections in BEX files
         if (bex_pars[gameepisode][gamemap])
@@ -2672,6 +2677,13 @@ G_InitNew
                 skytexturename = "SKY3";
             }
             break;
+          case 6:        // [crispy] Sigil II
+            skytexturename = "SKY6_ZD";
+            if (R_CheckTextureNumForName(DEH_String(skytexturename)) == -1)
+            {
+                skytexturename = "SKY3";
+            }
+            break;
         }
         skytexturename = DEH_String(skytexturename);
         skytexture = R_TextureNumForName(skytexturename);
diff --git a/src/doom/hu_stuff.c b/src/doom/hu_stuff.c
index 90656eac84..fa7aadd0d7 100644
--- a/src/doom/hu_stuff.c
+++ b/src/doom/hu_stuff.c
@@ -175,6 +175,17 @@ const char *mapnames[] =	// DOOM shareware/registered/retail (Ultimate) names.
     HUSTR_E5M8,
     HUSTR_E5M9,
 
+    // [crispy] Sigil II
+    HUSTR_E6M1,
+    HUSTR_E6M2,
+    HUSTR_E6M3,
+    HUSTR_E6M4,
+    HUSTR_E6M5,
+    HUSTR_E6M6,
+    HUSTR_E6M7,
+    HUSTR_E6M8,
+    HUSTR_E6M9,
+
     "NEWLEVEL",
     "NEWLEVEL",
     "NEWLEVEL",
diff --git a/src/doom/m_menu.c b/src/doom/m_menu.c
index 88ebc1699e..b3a4b31b4d 100644
--- a/src/doom/m_menu.c
+++ b/src/doom/m_menu.c
@@ -316,6 +316,7 @@ enum
     ep3,
     ep4,
     ep5, // [crispy] Sigil
+    ep6, // [crispy] Sigil II
     ep_end
 } episodes_e;
 
@@ -326,6 +327,17 @@ menuitem_t EpisodeMenu[]=
     {1,"M_EPI3", M_Episode,'i'},
     {1,"M_EPI4", M_Episode,'t'}
    ,{1,"M_EPI5", M_Episode,'s'} // [crispy] Sigil
+   ,{1,"M_EPI6", M_Episode,'s'} // [crispy] Sigil II
+};
+
+// [crispy] have Sigil II but not Sigil
+menuitem_t EpisodeMenuSII[]=
+{
+    {1,"M_EPI1", M_Episode,'k'},
+    {1,"M_EPI2", M_Episode,'t'},
+    {1,"M_EPI3", M_Episode,'i'},
+    {1,"M_EPI4", M_Episode,'t'}
+   ,{1,"M_EPI6", M_Episode,'s'} // [crispy] Sigil II
 };
 
 menu_t  EpiDef =
@@ -1352,6 +1364,9 @@ void M_Episode(int choice)
     }
 
     epi = choice;
+    // [crispy] have Sigil II loaded but not Sigil
+    if (epi == 4 && crispy->haved1e6 && !crispy->haved1e5)
+        epi = 5;
     M_SetupNextMenu(&NewDef);
 }
 
@@ -3294,10 +3309,18 @@ void M_Init (void)
     }
 
     // [crispy] Sigil
-    if (!crispy->haved1e5)
+    if (!crispy->haved1e5 && !crispy->haved1e6)
     {
         EpiDef.numitems = 4;
     }
+    else if (crispy->haved1e5 != crispy->haved1e6)
+    {
+        EpiDef.numitems = 5;
+        if (crispy->haved1e6)
+        {
+            EpiDef.menuitems = EpisodeMenuSII;
+        }
+    }
 
     // Versions of doom.exe before the Ultimate Doom release only had
     // three episodes; if we're emulating one of those then don't try
diff --git a/src/doom/p_enemy.c b/src/doom/p_enemy.c
index 26fc69b39d..97f6dde3a6 100644
--- a/src/doom/p_enemy.c
+++ b/src/doom/p_enemy.c
@@ -1720,6 +1720,10 @@ static boolean CheckBossEnd(mobjtype_t motype)
             case 5:
                 return (gamemap == 8 && !critical->havesigil);
 
+            // [crispy] no trigger for Sigil II E6
+            case 6:
+                return 0;
+
             default:
                 return gamemap == 8;
 	}
diff --git a/src/doom/s_sound.c b/src/doom/s_sound.c
index 5a6d8e44af..2bdb69cdc8 100644
--- a/src/doom/s_sound.c
+++ b/src/doom/s_sound.c
@@ -424,7 +424,7 @@ void S_Start(void)
             mus_e1m9,        // Tim          e4m9
         };
 
-        if (gameepisode < 4 || gameepisode == 5) // [crispy] Sigil
+        if (gameepisode < 4 || gameepisode == 5 || gameepisode == 6) // [crispy] Sigil
         {
             mnum = mus_e1m1 + (gameepisode-1)*9 + gamemap-1;
         }
diff --git a/src/doom/sounds.c b/src/doom/sounds.c
index 8d75a55a56..1f7c124da3 100644
--- a/src/doom/sounds.c
+++ b/src/doom/sounds.c
@@ -81,6 +81,16 @@ musicinfo_t S_music[] =
     MUSIC("e5m7"),
     MUSIC("e5m8"),
     MUSIC("e5m9"),
+    // [crispy] Sigil II
+    MUSIC("e6m1"),
+    MUSIC("e6m2"),
+    MUSIC("e6m3"),
+    MUSIC("e6m4"),
+    MUSIC("e6m5"),
+    MUSIC("e6m6"),
+    MUSIC("e6m7"),
+    MUSIC("e6m8"),
+    MUSIC("e6m9"),
     MUSIC("sigint"),
     MUSIC("inter"),
     MUSIC("intro"),
diff --git a/src/doom/sounds.h b/src/doom/sounds.h
index e49ecf088a..2928f34c3a 100644
--- a/src/doom/sounds.h
+++ b/src/doom/sounds.h
@@ -82,6 +82,16 @@ typedef enum
     mus_e5m7,
     mus_e5m8,
     mus_e5m9,
+    // [crispy] Sigil II
+    mus_e6m1,
+    mus_e6m2,
+    mus_e6m3,
+    mus_e6m4,
+    mus_e6m5,
+    mus_e6m6,
+    mus_e6m7,
+    mus_e6m8,
+    mus_e6m9,
     mus_sigint,
     mus_inter,
     mus_intro,
diff --git a/src/doom/st_stuff.c b/src/doom/st_stuff.c
index db1af4ee6e..a22ee89a4b 100644
--- a/src/doom/st_stuff.c
+++ b/src/doom/st_stuff.c
@@ -1187,7 +1187,8 @@ ST_Responder (event_t* ev)
           if (epsd > 4)
           {
               // [crispy] Sigil
-              if (!(crispy->haved1e5 && epsd == 5))
+              if (!(crispy->haved1e5 && epsd == 5) &&
+                  !(crispy->haved1e6 && epsd == 6))
               return false;
           }
           if (epsd == 4 && gameversion < exe_ultimate)
diff --git a/src/doom/wi_stuff.c b/src/doom/wi_stuff.c
index 1820cbd778..1a1c41f8dd 100644
--- a/src/doom/wi_stuff.c
+++ b/src/doom/wi_stuff.c
@@ -1555,7 +1555,7 @@ static boolean WI_drawParTime (void)
 		}
 
 		// [crispy] PWAD: par times for Sigil
-		if (wbs->epsd == 4)
+		if (wbs->epsd == 4 || wbs->epsd == 5)
 		{
 			result = true;
 		}
@@ -1875,6 +1875,10 @@ static void WI_loadUnloadData(load_callback_t callback)
     {
         M_StringCopy(name, DEH_String("SIGILINT"), sizeof(name));
     }
+    else if (crispy->haved1e6 && wbs->epsd == 5 && W_CheckNumForName(DEH_String("SIGILIN2")) != -1) // [crispy] Sigil
+    {
+        M_StringCopy(name, DEH_String("SIGILIN2"), sizeof(name));
+    }
     else
     {
 	DEH_snprintf(name, sizeof(name), "WIMAP%d", wbs->epsd);

From 53cc8b89152a0e227854bf58a93b6920da20f0c8 Mon Sep 17 00:00:00 2001
From: Michael Day <contact@michaelcday.com>
Date: Sat, 23 Dec 2023 11:09:17 -0500
Subject: [PATCH 2/4] doom: add sideload support for Sigil II

---
 src/crispy.h        |   1 +
 src/doom/d_main.c   |   2 +-
 src/doom/d_pwad.c   | 180 ++++++++++++++++++++++++++++++++++++++------
 src/doom/d_pwad.h   |   2 +-
 src/doom/f_finale.c |  14 +++-
 src/doom/g_game.c   |   8 ++
 src/doom/p_enemy.c  |   4 +-
 src/doom/sounds.c   |   1 +
 src/doom/sounds.h   |   1 +
 src/doom/wi_stuff.c |   3 +
 10 files changed, 186 insertions(+), 30 deletions(-)

diff --git a/src/crispy.h b/src/crispy.h
index 46460fc089..de6e702cc6 100644
--- a/src/crispy.h
+++ b/src/crispy.h
@@ -114,6 +114,7 @@ typedef struct
 	char *havenerve;
 	char *havemaster;
 	char *havesigil;
+	char *havesigil2;
 
 	const char *sdlversion;
 	const char *platform;
diff --git a/src/doom/d_main.c b/src/doom/d_main.c
index a08b9fc4b2..6afaf7b059 100644
--- a/src/doom/d_main.c
+++ b/src/doom/d_main.c
@@ -1993,7 +1993,7 @@ void D_DoomMain (void)
 	    gamevariant != freedoom &&
 	    strncasecmp(M_BaseName(iwadfile), "rekkr", 5))
 	{
-		D_LoadSigilWad();
+		D_LoadSigilWads();
 	}
 
 	if (gamemission == doom2)
diff --git a/src/doom/d_pwad.c b/src/doom/d_pwad.c
index 25b1542cfe..c886f939bf 100644
--- a/src/doom/d_pwad.c
+++ b/src/doom/d_pwad.c
@@ -28,16 +28,17 @@
 #include "m_misc.h"
 #include "w_main.h"
 #include "w_wad.h"
+#include "w_merge.h" // [crispy] W_MergeFile()
 
 extern char *iwadfile;
 
 // [crispy] auto-load SIGIL.WAD (and SIGIL_SHREDS.WAD) if available
-void D_LoadSigilWad (void)
+static boolean LoadSigilWad (const char *iwaddir, boolean pwadtexture)
 {
 	int i, j;
 	char *sigil_shreds = NULL;
 	const char *sigil_basename;
-	char *dirname, *autoload_dir;
+	char *autoload_dir;
 
 	const char *const sigil_wads[] = {
 		"SIGIL_v1_21.wad",
@@ -61,12 +62,6 @@ void D_LoadSigilWad (void)
 		{"D_INTRO",  "D_SIGTIT"},
 	};
 
-	const char *const texture_files[] = {
-		"PNAMES",
-		"TEXTURE1",
-		"TEXTURE2",
-	};
-
 	// [crispy] don't load SIGIL.WAD if another PWAD already provides E5M1
 	i = W_CheckNumForName("E5M1");
 	if (i != -1)
@@ -76,34 +71,27 @@ void D_LoadSigilWad (void)
 		{
 			crispy->havesigil = (char *)-1;
 		}
-		return;
+		return false;
 	}
 
 	// [crispy] don't load SIGIL.WAD if SIGIL_COMPAT.WAD is already loaded
 	i = W_CheckNumForName("E3M1");
 	if (i != -1 && !strncasecmp(W_WadNameForLump(lumpinfo[i]), "SIGIL_COMPAT", 12))
 	{
-		return;
+		return false;
 	}
 
-	// [crispy] don't load SIGIL.WAD if another PWAD already modifies the texture files
-	for (i = 0; i < arrlen(texture_files); i++)
+	if (pwadtexture)
 	{
-		j = W_CheckNumForName(texture_files[i]);
-
-		if (j != -1 && !W_IsIWADLump(lumpinfo[j]))
-		{
-			return;
-		}
+		return false;
 	}
 
-	dirname = M_DirName(iwadfile);
-	sigil_shreds = M_StringJoin(dirname, DIR_SEPARATOR_S, "SIGIL_SHREDS.WAD", NULL);
+	sigil_shreds = M_StringJoin(iwaddir, DIR_SEPARATOR_S, "SIGIL_SHREDS.WAD", NULL);
 
 	// [crispy] load SIGIL.WAD
 	for (i = 0; i < arrlen(sigil_wads); i++)
 	{
-		crispy->havesigil = M_StringJoin(dirname, DIR_SEPARATOR_S, sigil_wads[i], NULL);
+		crispy->havesigil = M_StringJoin(iwaddir, DIR_SEPARATOR_S, sigil_wads[i], NULL);
 
 		if (M_FileExists(crispy->havesigil))
 		{
@@ -118,12 +106,11 @@ void D_LoadSigilWad (void)
 			break;
 		}
 	}
-	free(dirname);
 
 	if (crispy->havesigil == NULL)
 	{
 		free(sigil_shreds);
-		return;
+		return false;
 	}
 
 	printf(" [Sigil] adding %s\n", crispy->havesigil);
@@ -183,8 +170,151 @@ void D_LoadSigilWad (void)
 		}
 	}
 
-	// [crispy] regenerate the hashtable
-	W_GenerateHashTable();
+	return true;
+}
+
+// [crispy] auto-load Sigil II
+static boolean LoadSigil2Wad (const char *iwaddir, boolean pwadtexture)
+{
+    int i, j;
+    const char *sigil2_basename;
+    char *autoload_dir;
+
+    const char *const sigil2_wads[] = {
+        "SIGIL_II_MP3_V1_0.WAD",
+        "SIGIL_II_V1_0.WAD",
+    };
+
+    static const struct {
+        const char *name;
+        const char new_name[8];
+    } sigil2_lumps [] = {
+        {"CREDIT",   "SG2CREDI"},
+        {"HELP1",    "SG2HELP1"},
+        {"TITLEPIC", "SG2TITLE"},
+        {"SIGILEND", "SGL2END"},
+        {"DEHACKED", "SG2_DEH"},
+        {"DEMO1",    "SG2DEMO1"},
+        {"DEMO2",    "SG2DEMO2"},
+        {"DEMO3",    "SG2DEMO3"},
+        {"DEMO4",    "SG2DEMO4"},
+        {"D_INTER",  "D_SG2INT"},
+        {"D_INTRO",  "D_SG2TIT"},
+    };
+
+    // [crispy] don't load Sigil II if another PWAD already provides E6M1
+    i = W_CheckNumForName("E6M1");
+    if (i != -1)
+    {
+        // [crispy] indicate that SIGIL_II_*.WAD is already loaded as a PWAD
+        if (!strncasecmp(W_WadNameForLump(lumpinfo[i]), "SIGIL_II", 8))
+        {
+            crispy->havesigil2 = (char *)-1;
+        }
+
+        return false;
+    }
+
+    // [crispy] don't load Sigil II if another PWAD already modifies the
+    // texture files
+    if (pwadtexture)
+    {
+        return false;
+    }
+
+    // [crispy] load Sigil II
+    for (i = 0; i < arrlen(sigil2_wads); i++)
+    {
+        crispy->havesigil2 = M_StringJoin(iwaddir, DIR_SEPARATOR_S,
+                                         sigil2_wads[i], NULL);
+
+        if (M_FileExists(crispy->havesigil2))
+        {
+            break;
+        }
+
+        free(crispy->havesigil2);
+        crispy->havesigil2 = D_FindWADByName(sigil2_wads[i]);
+
+        if (crispy->havesigil2)
+        {
+            break;
+        }
+    }
+
+    if (crispy->havesigil2 == NULL)
+    {
+        return false;
+    }
+
+    printf(" [Sigil II] adding %s\n", crispy->havesigil2);
+    W_MergeFile(crispy->havesigil2);
+    sigil2_basename = M_BaseName(crispy->havesigil2);
+
+    // [crispy] rename intrusive Sigil II graphics, demos and music lumps out
+    // of the way
+    for (i = 0; i < arrlen(sigil2_lumps); i++)
+    {
+        j = W_CheckNumForName(sigil2_lumps[i].name);
+
+        if (j != -1 && !strcasecmp(W_WadNameForLump(lumpinfo[j]), sigil2_basename))
+        {
+            memcpy(lumpinfo[j]->name, sigil2_lumps[i].new_name, 8);
+        }
+    }
+
+    // [crispy] load WAD and DEH files from autoload directories
+    if (!M_ParmExists("-noautoload"))
+    {
+        if ((autoload_dir = M_GetAutoloadDir(sigil2_basename, false)))
+        {
+            W_AutoLoadWADs(autoload_dir);
+            DEH_AutoLoadPatches(autoload_dir);
+            free(autoload_dir);
+        }
+    }
+
+    return true;
+}
+
+// [crispy] auto-load Sigil and Sigil II if available
+void D_LoadSigilWads (void)
+{
+    int i, j;
+    boolean sigilloaded, sigil2loaded;
+    boolean pwadtexture = false;
+    char *iwaddir;
+
+    const char *const texture_file[] = {
+        "PNAMES",
+        "TEXTURE1",
+        "TEXTURE2",
+    };
+
+    // [crispy] don't load Sigils if another PWAD already modifies the texture
+    // files
+    for (i = 0; i < arrlen(texture_file); i++)
+    {
+        j = W_CheckNumForName(texture_file[i]);
+
+        if (j != -1 && !W_IsIWADLump(lumpinfo[j]))
+        {
+            pwadtexture = true;
+            break;
+        }
+    }
+
+    iwaddir = M_DirName(iwadfile);
+    sigilloaded = LoadSigilWad(iwaddir, pwadtexture);
+    sigil2loaded = LoadSigil2Wad(iwaddir, pwadtexture);
+
+    if (sigilloaded || sigil2loaded)
+    {
+        // [crispy] regenerate the hashtable
+        W_GenerateHashTable();
+    }
+
+    free(iwaddir);
 }
 
 // [crispy] check if NERVE.WAD is already loaded as a PWAD
diff --git a/src/doom/d_pwad.h b/src/doom/d_pwad.h
index 0f05aeeba0..bb0a98eddf 100644
--- a/src/doom/d_pwad.h
+++ b/src/doom/d_pwad.h
@@ -21,7 +21,7 @@
 #ifndef __D_PWAD__
 #define __D_PWAD__
 
-void D_LoadSigilWad(void);
+void D_LoadSigilWads(void);
 void D_LoadNerveWad(void);
 void D_LoadMasterlevelsWad(void);
 
diff --git a/src/doom/f_finale.c b/src/doom/f_finale.c
index a7e0ea8964..a0b7cb180b 100644
--- a/src/doom/f_finale.c
+++ b/src/doom/f_finale.c
@@ -1013,13 +1013,25 @@ static void F_ArtScreenDrawer(void)
                 break;
             // [crispy] Sigil
             case 5:
-            case 6:
                 lumpname = "SIGILEND";
                 if (W_CheckNumForName(DEH_String(lumpname)) == -1)
                 {
                     return;
                 }
                 break;
+            // [crispy] Sigil II
+            case 6:
+                lumpname = "SGL2END";
+                if (W_CheckNumForName(DEH_String(lumpname)) == -1)
+                {
+                    lumpname = "SIGILEND";
+
+                    if (W_CheckNumForName(DEH_String(lumpname)) == -1)
+                    {
+                        return;
+                    }
+                }
+                break;
             default:
                 return;
         }
diff --git a/src/doom/g_game.c b/src/doom/g_game.c
index 9fbda51a32..e4c9479b2e 100644
--- a/src/doom/g_game.c
+++ b/src/doom/g_game.c
@@ -2586,6 +2586,14 @@ G_InitNew
 
     M_ClearRandom ();
 
+    // [crispy] Spider Mastermind gets increased health in Sigil II. Normally
+    // the Sigil II DEH handles this, but we don't load the DEH if the WAD gets
+    // sideloaded.
+    if (crispy->havesigil2 && crispy->havesigil2 != (char *)-1)
+    {
+        mobjinfo[MT_SPIDER].spawnhealth = (episode == 6) ? 9000 : 3000;
+    }
+
     if (skill == sk_nightmare || respawnparm )
 	respawnmonsters = true;
     else
diff --git a/src/doom/p_enemy.c b/src/doom/p_enemy.c
index 97f6dde3a6..ad5a62ab92 100644
--- a/src/doom/p_enemy.c
+++ b/src/doom/p_enemy.c
@@ -1720,9 +1720,9 @@ static boolean CheckBossEnd(mobjtype_t motype)
             case 5:
                 return (gamemap == 8 && !critical->havesigil);
 
-            // [crispy] no trigger for Sigil II E6
+            // [crispy] no trigger for auto-loaded Sigil II E6
             case 6:
-                return 0;
+                return (gamemap == 8 && !critical->havesigil2);
 
             default:
                 return gamemap == 8;
diff --git a/src/doom/sounds.c b/src/doom/sounds.c
index 1f7c124da3..8f30172282 100644
--- a/src/doom/sounds.c
+++ b/src/doom/sounds.c
@@ -92,6 +92,7 @@ musicinfo_t S_music[] =
     MUSIC("e6m8"),
     MUSIC("e6m9"),
     MUSIC("sigint"),
+    MUSIC("sg2int"),
     MUSIC("inter"),
     MUSIC("intro"),
     MUSIC("bunny"),
diff --git a/src/doom/sounds.h b/src/doom/sounds.h
index 2928f34c3a..399029b577 100644
--- a/src/doom/sounds.h
+++ b/src/doom/sounds.h
@@ -93,6 +93,7 @@ typedef enum
     mus_e6m8,
     mus_e6m9,
     mus_sigint,
+    mus_sg2int,
     mus_inter,
     mus_intro,
     mus_bunny,
diff --git a/src/doom/wi_stuff.c b/src/doom/wi_stuff.c
index 1a1c41f8dd..f2c34a0049 100644
--- a/src/doom/wi_stuff.c
+++ b/src/doom/wi_stuff.c
@@ -1676,6 +1676,9 @@ void WI_Ticker(void)
 	// [crispy] Sigil
 	else if (crispy->haved1e5 && wbs->epsd == 4 && W_CheckNumForName(DEH_String("D_SIGINT")) != -1)
 	  S_ChangeMusic(mus_sigint, true);
+	// [crispy] Sigil II
+	else if (crispy->haved1e6 && wbs->epsd == 5 && W_CheckNumForName(DEH_String("D_SG2INT")) != -1)
+	  S_ChangeMusic(mus_sg2int, true);
 	else
 	  S_ChangeMusic(mus_inter, true); 
     }

From 589b56f7234dc1336cbc1e75a5d7428804e7e010 Mon Sep 17 00:00:00 2001
From: Michael Day <contact@michaelcday.com>
Date: Sun, 24 Dec 2023 21:23:26 -0500
Subject: [PATCH 3/4] doom: next level key supports Sigil II

---
 src/doom/m_menu.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/doom/m_menu.c b/src/doom/m_menu.c
index b3a4b31b4d..b0e11d1405 100644
--- a/src/doom/m_menu.c
+++ b/src/doom/m_menu.c
@@ -2169,12 +2169,13 @@ static int G_ReloadLevel(void)
 
 static int G_GotoNextLevel(void)
 {
-  byte doom_next[5][9] = {
+  byte doom_next[6][9] = {
     {12, 13, 19, 15, 16, 17, 18, 21, 14},
     {22, 23, 24, 25, 29, 27, 28, 31, 26},
     {32, 33, 34, 35, 36, 39, 38, 41, 37},
     {42, 49, 44, 45, 46, 47, 48, 51, 43},
-    {52, 53, 54, 55, 56, 59, 58, 11, 57},
+    {52, 53, 54, 55, 56, 59, 58, 61, 57},
+    {62, 63, 69, 65, 66, 67, 68, 11, 64},
   };
   byte doom2_next[33] = {
      2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
@@ -2217,8 +2218,13 @@ static int G_GotoNextLevel(void)
       if (gamemode == registered)
         doom_next[2][7] = 11;
 
-      if (!crispy->haved1e5)
+      // [crispy] Sigil and Sigil II
+      if (!crispy->haved1e5 && !crispy->haved1e6)
         doom_next[3][7] = 11;
+      else if (!crispy->haved1e5 && crispy->haved1e6)
+        doom_next[3][7] = 61;
+      else if (crispy->haved1e5 && !crispy->haved1e6)
+        doom_next[4][7] = 11;
 
       if (gameversion == exe_chex)
       {

From e1dc4d5eae9f1fe78f84b899088d869aad628fdc Mon Sep 17 00:00:00 2001
From: Michael Day <contact@michaelcday.com>
Date: Sun, 24 Dec 2023 21:25:32 -0500
Subject: [PATCH 4/4] doom: properly init Sigil II music

---
 src/doom/s_sound.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/doom/s_sound.c b/src/doom/s_sound.c
index 2bdb69cdc8..23a1379ddd 100644
--- a/src/doom/s_sound.c
+++ b/src/doom/s_sound.c
@@ -294,7 +294,7 @@ void S_Init(int sfxVolume, int musicVolume)
     I_AtExit(S_Shutdown, true);
 
     // [crispy] initialize dedicated music tracks for the 4th episode
-    for (i = mus_e4m1; i <= mus_e5m9; i++)
+    for (i = mus_e4m1; i <= mus_e6m9; i++)
     {
         musicinfo_t *const music = &S_music[i];
         char namebuf[9];