From 23b235b85f601db91ecce8a4ab197f0865a6c027 Mon Sep 17 00:00:00 2001
From: DizzyEggg <jajkodizzy@wp.pl>
Date: Tue, 18 Nov 2025 12:51:01 +0100
Subject: [PATCH 1/2] some stuff

---
 include/dungeon_cutscenes.h |  2 +-
 include/effect_main.h       | 12 +++--------
 src/code_800D090.c          |  9 +++-----
 src/code_8040094_1.c        | 23 +++-----------------
 src/effect_main.c           | 26 +++++++++++------------
 src/ground_bg.c             | 42 ++++++++++++++++++-------------------
 src/ground_main.c           |  6 ++----
 src/random.c                |  2 +-
 8 files changed, 47 insertions(+), 75 deletions(-)

diff --git a/include/dungeon_cutscenes.h b/include/dungeon_cutscenes.h
index 36ca6ef9c..175306b38 100644
--- a/include/dungeon_cutscenes.h
+++ b/include/dungeon_cutscenes.h
@@ -55,7 +55,7 @@ void ZapdosReFightDialogue(void);
 void nullsub_100(u8, u8, u8);
 void sub_8086B14(void);
 void sub_8086B94(void);
-void sub_8086BDC(u8, s32); // TODO: should be u8
+void sub_8086BDC(u8, u8);
 void sub_8086E40(void);
 void sub_8086E9C(void);
 void sub_8086F00(void);
diff --git a/include/effect_main.h b/include/effect_main.h
index 77a0cbbd6..84135747b 100644
--- a/include/effect_main.h
+++ b/include/effect_main.h
@@ -17,12 +17,6 @@ typedef struct unkStruct_80416E0
     unkStruct_2039DB0 spriteMasks;
 } unkStruct_80416E0;
 
-typedef struct unkStruct_800EA44
-{
-    s16 unk0;
-    s16 unk2;
-} unkStruct_800EA44;
-
 struct UnkStruct_8040094
 {
     u16 unk0;
@@ -47,8 +41,8 @@ s32 sub_800E6D8(s32 a0);
 s32 sub_800E700(s32 a0);
 s32 sub_800E710(s32 species, s32 moveId);
 s32 sub_800E790(s32 a0_, s32 a1);
-bool8 sub_800E7D0(u16 *param_1);
-bool8 sub_800E838(u16 *param_1, s32 param_2);
+bool8 sub_800E7D0(struct UnkStruct_8040094 *param_1);
+bool8 sub_800E838(struct UnkStruct_8040094 *param_1, s32 param_2);
 s32 sub_800E890(unkStruct_80416E0 *param_1);
 void sub_800E8AC(s32 a0, DungeonPos *a1, DungeonPos *a2, s32 a3, unkStruct_2039DB0 *a4);
 bool8 sub_800E90C(DungeonPos *param_1);
@@ -56,7 +50,7 @@ void sub_800E970(void);
 bool8 sub_800E9A8(s32 a0);
 bool8 sub_800E9E4(u32 param_1);
 bool8 sub_800E9FC(u8 a0);
-u8 sub_800EA44(unkStruct_800EA44 param_1, s32 param_2);
+u8 sub_800EA44(s32 monsterId_, s32 param_2);
 s32 sub_800EA84(struct UnkStruct_8040094 *a0);
 void sub_800EB24(s32 param_1, DungeonPos *param_2, DungeonPos *param_3, s32 r5, s32 r4);
 s32 sub_800EBC8(struct UnkStruct_8040094 *a0);
diff --git a/src/code_800D090.c b/src/code_800D090.c
index b39a41cfa..b9309b2a9 100644
--- a/src/code_800D090.c
+++ b/src/code_800D090.c
@@ -11,8 +11,7 @@ void Hang(void)
     }
 }
 
-// Unused
-void sub_800D098(void)
+UNUSED static void sub_800D098(void)
 {
     u32 dispcnt_save;
     u32 ie_store;
@@ -71,8 +70,7 @@ void sprintfStatic(char *buffer, const char *text, ...)
     va_end(vArgv);
 }
 
-// Unused
-void sub_800D16C(const char *text, ...)
+UNUSED static void sub_800D16C(const char *text, ...)
 {
     char buffer[1024];
     va_list vArgv;
@@ -81,8 +79,7 @@ void sub_800D16C(const char *text, ...)
     va_end(vArgv);
 }
 
-// Unused
-void sub_800D10A(const char *r0, u32 r1, u32 r2, u32 r3, ...)
+UNUSED static void sub_800D10A(const char *r0, u32 r1, u32 r2, u32 r3, ...)
 {
 }
 
diff --git a/src/code_8040094_1.c b/src/code_8040094_1.c
index e671e6dea..c9f236d94 100644
--- a/src/code_8040094_1.c
+++ b/src/code_8040094_1.c
@@ -13,43 +13,26 @@
 #include "dungeon_info.h"
 #include "dungeon_message.h"
 #include "dungeon_move.h"
+#include "dungeon_move_util.h"
 #include "dungeon_music.h"
 #include "dungeon_random.h"
 #include "dungeon_util.h"
+#include "dungeon_logic.h"
 #include "sprite.h"
 #include "weather.h"
 #include "dungeon_map_access.h"
 #include "dungeon_strings.h"
 #include "dungeon_mon_sprite_render.h"
 #include "dungeon_8041AD0.h"
-
-struct UnkStruct_8040094
-{
-    u16 unk0;
-    u16 unk2;
-    DungeonPos unk4;
-    DungeonPos unk8;
-    s32 unkC;
-    s32 unk10;
-};
+#include "effect_main.h"
 
 extern u8 sub_800EC94(s32 param_1);
-extern s32 sub_800E710(s32 species, u16 moveId);
 extern void sub_800EEC8(u16 r0);
-extern u8 sub_800EA44(s32 species, u16 a2);
-extern s32 sub_800E790(s32 species, u16 a2);
-extern s32 sub_800E52C(struct UnkStruct_8040094 *a0);
-extern s32 sub_800EA84(struct UnkStruct_8040094 *a0);
-extern bool8 sub_800E838(struct UnkStruct_8040094 *a0, s32 a1);
 extern bool8 sub_800E9A8(s32 a0);
 extern void sub_800EEF8(u16 a0);
 extern bool8 sub_803F428(DungeonPos *pos);
 extern void sub_800EEE0(u16 a0);
-extern s32 sub_800EBC8(struct UnkStruct_8040094 *a0);
-extern bool8 sub_800E7D0(struct UnkStruct_8040094 *a0);
 extern bool8 EffectiveMoveHasSineWobble(s32 moveId);
-extern bool8 MoveMatchesBideClassStatus(Entity *pokemon, Move *move);
-extern bool8 IsMonsterSleeping(Entity *pokemon);
 
 extern const s32 gUnknown_8106A8C[];
 
diff --git a/src/effect_main.c b/src/effect_main.c
index cb786cc81..dd3e245ed 100644
--- a/src/effect_main.c
+++ b/src/effect_main.c
@@ -925,16 +925,16 @@ s32 sub_800E790(s32 species_, s32 moveId)
     return unkPtr1->soundEffectId;
 }
 
-bool8 sub_800E7D0(u16 *param_1)
+bool8 sub_800E7D0(struct UnkStruct_8040094 *param_1)
 {
     s32 local_1c[4];
     s32 index;
     bool8 flag = FALSE;
 
-    local_1c[0] = sub_800ECB8(*param_1)->unk0;
-    local_1c[1] = sub_800ECB8(*param_1)->unk2;
-    local_1c[2] = sub_800ECB8(*param_1)->unk4;
-    local_1c[3] = sub_800ECB8(*param_1)->unk6;
+    local_1c[0] = sub_800ECB8(param_1->unk0)->unk0;
+    local_1c[1] = sub_800ECB8(param_1->unk0)->unk2;
+    local_1c[2] = sub_800ECB8(param_1->unk0)->unk4;
+    local_1c[3] = sub_800ECB8(param_1->unk0)->unk6;
     for (index = 0; index < 4; index++) {
         flag = (sub_800ECA4(local_1c[index])->animType == 4);
         if (flag)
@@ -943,14 +943,14 @@ bool8 sub_800E7D0(u16 *param_1)
     return flag;
 }
 
-bool8 sub_800E838(u16 *param_1, s32 param_2)
+bool8 sub_800E838(struct UnkStruct_8040094 *param_1, s32 param_2)
 {
     s32 local_1c[4];
 
-    local_1c[0] = sub_800ECB8(*param_1)->unk0;
-    local_1c[1] = sub_800ECB8(*param_1)->unk2;
-    local_1c[2] = sub_800ECB8(*param_1)->unk4;
-    local_1c[3] = sub_800ECB8(*param_1)->unk6;
+    local_1c[0] = sub_800ECB8(param_1->unk0)->unk0;
+    local_1c[1] = sub_800ECB8(param_1->unk0)->unk2;
+    local_1c[2] = sub_800ECB8(param_1->unk0)->unk4;
+    local_1c[3] = sub_800ECB8(param_1->unk0)->unk6;
     return sub_800ECA4(local_1c[param_2])->animType == 4;
 }
 
@@ -1065,15 +1065,15 @@ bool8 sub_800E9FC(u8 a0)
     return FALSE;
 }
 
-u8 sub_800EA44(unkStruct_800EA44 param_1, s32 param_2)
+u8 sub_800EA44(s32 monsterId_, s32 param_2)
 {
     s32 i;
-    s32 a = param_1.unk0;
+    s32 monsterId = (s16) monsterId_;
     const unkStruct_80BDBC4 *ret = sub_800ECB8(param_2);
     const unkStruct_80C183C *unkStruct2 = sub_800ECD0(ret->unk20);
 
     for (i = 0; i < ret->unk1C; i++, unkStruct2++) {
-        if (unkStruct2->species == a) {
+        if (unkStruct2->species == monsterId) {
             return unkStruct2->unk2;
         }
     }
diff --git a/src/ground_bg.c b/src/ground_bg.c
index 312f0150d..9bb2a8204 100644
--- a/src/ground_bg.c
+++ b/src/ground_bg.c
@@ -11,6 +11,7 @@
 #include "debug.h"
 #include "bg_control.h"
 #include "unk_dungeon_load.h"
+#include "palette_fade_util.h"
 #include "constants/dungeon.h"
 
 // This file most likely deals with map loading and writing to VRAM. It even has a custom decompression function.
@@ -32,7 +33,6 @@ static void ClearDoubleBgTilemaps(MapRender *mapRender);
 static void RenderChunksToBgTilemaps_2x2(MapRender *mapRender);
 static void RenderChunksToBgTilemaps_3x3(MapRender *mapRender);
 
-extern void sub_8003810(u16 param_1, RGB_Union param_2);
 extern void sub_809971C(u16 idx, const RGB_Array *strPtrs, s32 n);
 
 static const PixelPos sPositionZero = {0, 0};
@@ -199,8 +199,8 @@ void sub_80A2E64(GroundBg *groundBg)
 
     r6 = groundBg->unk52C.unk0 * 16;
     for (i = 0; i < groundBg->unk52C.unk2; i++) {
-        RGB_Union str1 = {0};
-        RGB_Union str2 = {0xFF, 0xFF, 0xFF, 0};
+        RGB_Array str1 = {0};
+        RGB_Array str2 = {0xFF, 0xFF, 0xFF, 0};
 
         sub_8003810(r6++, str1);
         for (j = 0; j < 15; j++) {
@@ -225,8 +225,8 @@ void sub_80A2FBC(GroundBg *groundBg, s32 mapFileId_)
     const void *bmaData;
     const void *bplData;
     BmaHeader *bmaHeader;
-    RGB_Union str2;
-    RGB_Union str1;
+    RGB_Array str2;
+    RGB_Array str1;
     const RGB_Array *rgbPal;
     s32 unk0Id;
     s32 id;
@@ -278,11 +278,11 @@ void sub_80A2FBC(GroundBg *groundBg, s32 mapFileId_)
 
     rgbPal = bplData;
     r5 = groundBg->unk52C.unk0 * 16;
-    str2 = (RGB_Union) {0};
-    str1.asArr.c[0] = 0xff;
-    str1.asArr.c[1] = 0xff;
-    str1.asArr.c[2] = 0xff;
-    str1.asArr.c[3] = 0;
+    str2 = (RGB_Array) {0};
+    str1.c[0] = 0xff;
+    str1.c[1] = 0xff;
+    str1.c[2] = 0xff;
+    str1.c[3] = 0;
     for (i = 0; i < bplHeader->numPalettes && i < groundBg->unk52C.unk2; i++) {
         sub_8003810(r5++, str2);
         sub_809971C(r5, rgbPal, 15);
@@ -474,21 +474,21 @@ void sub_80A3440(GroundBg *groundBg, s32 mapFileId_, const DungeonLocation *dung
     groundBg->bplHeader.hasPalAnimations = FALSE;
     if (groundBg->unk43C != NULL) {
         s32 i, j;
-        const RGB_Union *strPtr = groundBg->unk43C->data;
+        const RGB_Array *strPtr = groundBg->unk43C->data;
         u16 r7 = 0;
-        RGB_Union str0 = {0};
-        RGB_Union str1;
+        RGB_Array str0 = {0};
+        RGB_Array str1;
 
-        str1.asArr.c[0] = 0xff;
-        str1.asArr.c[1] = 0xff;
-        str1.asArr.c[2] = 0xff;
-        str1.asArr.c[3] = 0;
+        str1.c[0] = 0xff;
+        str1.c[1] = 0xff;
+        str1.c[2] = 0xff;
+        str1.c[3] = 0;
 
         for (i = 0; i < 12 && i < groundBg->unk52C.unk2; i++) {
             sub_8003810(r7++, str0);
             strPtr++;
             for (j = 0; j < 15; j++) {
-                RGB_Union str2 = {strPtr->asArr.c[0], strPtr->asArr.c[1], strPtr->asArr.c[2], strPtr->asArr.c[3]};
+                RGB_Array str2 = {strPtr->c[0], strPtr->c[1], strPtr->c[2], strPtr->c[3]};
                 sub_8003810(r7++, str2);
                 strPtr++;
             }
@@ -1360,7 +1360,7 @@ void sub_80A4764(GroundBg *groundBg)
                 }
 
                 if (sub0Ptr->unk8 != NULL) {
-                    RGB_Union empty = {0};
+                    RGB_Array empty = {0};
                     sub_8003810(r6, empty);
                     sub_809971C(r6 + 1, sub0Ptr->unk8, 15);
                     sub0Ptr->unk8 += 60;
@@ -1376,7 +1376,7 @@ void sub_80A4764(GroundBg *groundBg)
         s32 r6 = 160;
 
         for (i = 0; i < 32; i++, unkE0Ptr++, r6++) {
-            RGB_Union color;
+            RGB_Array color;
 
             if (sub_8004D14(unkE0Ptr, 1) && !sub_8004D40(unkE0Ptr, 1) && --unkE0Ptr->unk6 <= 0) {
                 unkE0Ptr->unk6 = unkE0Ptr->unk4;
@@ -1384,7 +1384,7 @@ void sub_80A4764(GroundBg *groundBg)
                     unkE0Ptr->unkC = unkE0Ptr->unk8;
                 }
                 unkE0Ptr->unk14 = *unkE0Ptr->unkC++;
-                color = (RGB_Union) {unkE0Ptr->unk14.r, unkE0Ptr->unk14.g, unkE0Ptr->unk14.b, unkE0Ptr->unk14.unk4};
+                color = (RGB_Array) {unkE0Ptr->unk14.r, unkE0Ptr->unk14.g, unkE0Ptr->unk14.b, unkE0Ptr->unk14.unk4};
                 sub_8003810(r6, color);
             }
         }
diff --git a/src/ground_main.c b/src/ground_main.c
index 63bc905ec..093c5c70f 100644
--- a/src/ground_main.c
+++ b/src/ground_main.c
@@ -33,6 +33,7 @@
 #include "code_809D148.h"
 #include "adventure_info.h"
 #include "palette_util.h"
+#include "code_800558C.h"
 
 EWRAM_DATA u32 gUnknown_20398A8 = {0};
 EWRAM_DATA s32 gUnknown_20398AC = {0};
@@ -59,8 +60,6 @@ extern void nullsub_106();
 extern void sub_80A73EC();
 extern void sub_8095494(DungeonMailSeed *param_1, u8 index);
 
-extern u16 gUnknown_2026E4E;
-
 // TODO: Move these externs to headers
 extern s16 sub_80A2654(s16 r0);
 extern bool8 sub_80048BC(void);
@@ -76,7 +75,6 @@ extern void sub_80060EC(void);
 extern void sub_809977C(void);
 extern void UpdateFadeInTile(s32);
 extern void sub_8001D88(void);
-extern void sub_8005838(s32, s32);
 
 static s16 sub_8098FCC(u32 unused);
 
@@ -271,7 +269,7 @@ u32 xxx_script_related_8098468(s32 param_1)
             GroundMap_ExecuteEvent(0x66,0);
         }
         GroundMap_Action();
-        sub_8005838(0,0);
+        sub_8005838(NULL,0);
         sub_80060EC();
         xxx_call_update_bg_sound_input();
         while ( 1 ) {
diff --git a/src/random.c b/src/random.c
index 9ee169816..fd2bf240e 100644
--- a/src/random.c
+++ b/src/random.c
@@ -46,4 +46,4 @@ void SetRNGSeed(s32 state)
 {
     sPRNGState = state;
     sPRNGState = Rand32Bit();
-}
\ No newline at end of file
+}

From fbbaee3c7f6e116fe58521052881a4853cf40c61 Mon Sep 17 00:00:00 2001
From: DizzyEggg <jajkodizzy@wp.pl>
Date: Tue, 18 Nov 2025 13:41:32 +0100
Subject: [PATCH 2/2] more externs

---
 include/code_800D090_1.h        |  5 +++-
 include/code_803C1B4.h          |  9 +++++++
 include/friend_list.h           |  1 +
 include/m4a.h                   |  4 ++--
 include/mailbox.h               |  5 ++--
 include/pelipper_board.h        |  3 +++
 include/thank_you_wonder_mail.h |  2 ++
 src/code_800D090_1.c            | 42 ++++++++++++++++-----------------
 src/code_803C1B4.c              |  2 +-
 src/code_80958E8.c              |  3 +--
 src/friend_rescue.c             |  6 ++---
 src/m4a.c                       |  3 ++-
 src/mailbox.c                   |  2 +-
 src/pelipper_board.c            |  4 ++--
 src/save.c                      |  4 +---
 src/textbox.c                   |  6 ++---
 src/thank_you_wonder_mail.c     |  6 ++---
 src/wonder_mail.c               |  3 +--
 src/wonder_mail_2.c             |  4 +---
 19 files changed, 63 insertions(+), 51 deletions(-)
 create mode 100644 include/code_803C1B4.h

diff --git a/include/code_800D090_1.h b/include/code_800D090_1.h
index e35e3b4d9..1a5707a42 100644
--- a/include/code_800D090_1.h
+++ b/include/code_800D090_1.h
@@ -2,5 +2,8 @@
 #define GUARD_CODE_800D090_1_H
 
 bool8 sub_800DAAC(void);
+bool8 sub_800DAB0(u16 sector, u8* dest, s32 size);
+bool8 sub_800DAB4(u16 sector, u8* src, s32 size);
+bool8 sub_800DAB8(void);
 
-#endif // GUARD_CODE_800D090_1_H
\ No newline at end of file
+#endif // GUARD_CODE_800D090_1_H
diff --git a/include/code_803C1B4.h b/include/code_803C1B4.h
new file mode 100644
index 000000000..62e2295ef
--- /dev/null
+++ b/include/code_803C1B4.h
@@ -0,0 +1,9 @@
+#ifndef GUARD_CODE_803C1B4_H
+#define GUARD_CODE_803C1B4_H
+
+#include "structs/str_dungeon_location.h"
+
+void sub_803C37C(DungeonLocation *location, u8 r1, u8 *itemReward);
+u32 GetDungeonTeamRankPts(DungeonLocation *dungeon, u8 r1);
+
+#endif // GUARD_CODE_803C1B4_H
diff --git a/include/friend_list.h b/include/friend_list.h
index b65491433..8b6c7e8e9 100644
--- a/include/friend_list.h
+++ b/include/friend_list.h
@@ -26,6 +26,7 @@ u32 FriendList_HandleInput(bool8);
 s32 FriendList_GetCurrId(void);
 void sub_8023B7C(bool8 addCursor);
 void FriendList_Free(void);
+struct unkStruct_3001B60 *FriendList_GetPtr(void);
 void FriendList_ShowWindow(void);
 bool8 sub_8024108(s32);
 
diff --git a/include/m4a.h b/include/m4a.h
index 0bc7988ff..ac4caba7d 100644
--- a/include/m4a.h
+++ b/include/m4a.h
@@ -13,7 +13,7 @@ void m4aSongNumStartOrChange(u16 n);
 void m4aSongNumStop(u16 n);
 void m4aMPlayAllStop(void);
 void m4aMPlayContinue(struct MusicPlayerInfo *mplayInfo);
-void m4aMPlayFadeOut(struct MusicPlayerInfo *mplayInfo, u32 speed);
+void m4aMPlayFadeOut(struct MusicPlayerInfo *mplayInfo, u16 speed);
 void m4aMPlayFadeOutTemporarily(struct MusicPlayerInfo *mplayInfo, u16 speed);
 void m4aMPlayFadeIn(struct MusicPlayerInfo *mplayInfo, u16 speed);
 void m4aMPlayImmInit(struct MusicPlayerInfo *mplayInfo);
@@ -21,7 +21,7 @@ void m4aMPlayStop(struct MusicPlayerInfo *mplayInfo);
 void m4aMPlayVolumeControl(struct MusicPlayerInfo *mplayInfo, u16 trackBits, u16 volume);
 void m4aSoundVSync(void);
 
-extern struct MusicPlayerInfo gMPlayInfo_BGM; // BGM??
+extern struct MusicPlayerInfo gMPlayInfo_BGM;
 extern struct MusicPlayerInfo gMPlayInfo_Fanfare;
 extern struct MusicPlayerInfo gMPlayInfo_SE1;
 extern struct MusicPlayerInfo gMPlayInfo_SE2;
diff --git a/include/mailbox.h b/include/mailbox.h
index 138537de5..44b89edda 100644
--- a/include/mailbox.h
+++ b/include/mailbox.h
@@ -1,5 +1,5 @@
 #ifndef GUARD_MAILBOX_H
-#define GUARD_MAILBOX_H 
+#define GUARD_MAILBOX_H
 
 #include "structs/menu.h"
 #include "structs/str_text.h"
@@ -22,7 +22,8 @@ struct unkStruct_203B304
     WindowTemplates unk10C;
 };
 
-extern void SetMailboxState(u32);
+u8 sub_802DFB0(void);
+void SetMailboxState(u32);
 
 enum MailBoxStates
 {
diff --git a/include/pelipper_board.h b/include/pelipper_board.h
index b1f31c58e..a33221a7d 100644
--- a/include/pelipper_board.h
+++ b/include/pelipper_board.h
@@ -41,4 +41,7 @@ enum PelipperBoardActions
     PELIPPER_BOARD_ACCEPT,
     PELIPPER_BOARD_INFO,
 };
+
+bool8 sub_802E864(void);
+
 #endif // GUARD_PELIPPER_BOARD_H
diff --git a/include/thank_you_wonder_mail.h b/include/thank_you_wonder_mail.h
index 5898cccad..4dea1d84f 100644
--- a/include/thank_you_wonder_mail.h
+++ b/include/thank_you_wonder_mail.h
@@ -33,4 +33,6 @@ typedef struct WonderMailStruct_203B2C4
     unkStruct_802F204 unk53C;
 } WonderMailStruct_203B2C4;
 
+bool8 CreateThankYouMailPelipper(void);
+
 #endif // GUARD_THANK_YOU_WONDER_MAIL_H
diff --git a/src/code_800D090_1.c b/src/code_800D090_1.c
index 9e900775e..ba5124666 100644
--- a/src/code_800D090_1.c
+++ b/src/code_800D090_1.c
@@ -1,46 +1,46 @@
 #include "global.h"
 #include "code_800D090_1.h"
 
-void nullsub_189(void)
+UNUSED static void nullsub_189(void)
 {}
 
-void nullsub_190(void)
+UNUSED static void nullsub_190(void)
 {}
 
-void nullsub_191(void)
+UNUSED static void nullsub_191(void)
 {}
 
-void nullsub_192(void)
+UNUSED static void nullsub_192(void)
 {}
 
-void nullsub_193(void)
+UNUSED static void nullsub_193(void)
 {}
 
-void nullsub_194(void)
+UNUSED static void nullsub_194(void)
 {}
 
-void nullsub_195(void)
+UNUSED static void nullsub_195(void)
 {}
 
-u32 sub_800DA94(void) {
+UNUSED static u32 sub_800DA94(void) {
     return 0;
 }
 
-u32 sub_800DA98(void) {
+UNUSED static u32 sub_800DA98(void) {
     return 0;
 }
 
-u32 sub_800DA9C(void) {
+UNUSED static u32 sub_800DA9C(void) {
     return 0;
 }
 
-void nullsub_196(void)
+UNUSED static void nullsub_196(void)
 {}
 
-void nullsub_197(void)
+UNUSED static void nullsub_197(void)
 {}
 
-void nullsub_198(void)
+UNUSED static void nullsub_198(void)
 {}
 
 bool8 sub_800DAAC(void)
@@ -48,18 +48,18 @@ bool8 sub_800DAAC(void)
     return FALSE;
 }
 
-u32 sub_800DAB0(void) {
-    return 0;
+bool8 sub_800DAB0(u16 sector, u8* dest, s32 size) {
+    return FALSE;
 }
 
-u32 sub_800DAB4(void) {
-    return 0;
+bool8 sub_800DAB4(u16 sector, u8* src, s32 size) {
+    return FALSE;
 }
 
-u32 sub_800DAB8(void) {
-    return 0;
+bool8 sub_800DAB8(void) {
+    return FALSE;
 }
 
-u32 sub_800DABC(void) {
-    return 0;
+UNUSED static bool8 sub_800DABC(void) {
+    return FALSE;
 }
diff --git a/src/code_803C1B4.c b/src/code_803C1B4.c
index a24dbb409..0fe615b57 100644
--- a/src/code_803C1B4.c
+++ b/src/code_803C1B4.c
@@ -1,4 +1,5 @@
 #include "global.h"
+#include "code_803C1B4.h"
 #include "structs/str_wonder_mail.h"
 #include "dungeon_info.h"
 #include "event_flag.h"
@@ -6,7 +7,6 @@
 
 extern u8 *gMissionRankText[];
 extern s32 gUnknown_80E80A0[];
-void sub_803C37C(DungeonLocation *, u8, u8 *);
 
 s32 sub_803C1B4(DungeonLocation *dungeon, u8 missionType)
 {
diff --git a/src/code_80958E8.c b/src/code_80958E8.c
index c0baa86fa..4185a68b2 100644
--- a/src/code_80958E8.c
+++ b/src/code_80958E8.c
@@ -17,8 +17,7 @@
 #include "pokemon_mail.h"
 #include "event_flag.h"
 #include "rescue_team_info.h"
-
-extern void sub_803C37C(struct DungeonLocation *, u8, u8 *);
+#include "code_803C1B4.h"
 
 bool8 sub_8095E38(WonderMail *mail, u8 dungeon, u32 floor, u8 param_4);
 u8 sub_8095F28(u8 param_1);
diff --git a/src/friend_rescue.c b/src/friend_rescue.c
index 7e53bc290..25d703b92 100644
--- a/src/friend_rescue.c
+++ b/src/friend_rescue.c
@@ -28,6 +28,7 @@
 #include "wonder_mail_4.h"
 #include "wonder_mail_5.h"
 #include "naming_screen.h"
+#include "code_803C1B4.h"
 
 extern void SetFriendRescueMenuState(u32);
 
@@ -584,11 +585,8 @@ extern u32 sub_8039068(u32, u8 *passwordBuffer, unkStruct_203B480 *r0);
 
 extern void sub_8031E10(void);
 extern u8 sub_800D588(void);
-extern u32 FriendList_GetPtr(void);
 extern bool8 sub_8031D70(u32 mailIndex, s32);
 
-extern u32 GetDungeonTeamRankPts(DungeonLocation *, u32);
-
 u32 CreateFriendRescueMenu(void)
 {
   char *monName;
@@ -1174,7 +1172,7 @@ void sub_8032828(void)
             CreateDialogueBoxAndPortrait(&gUnknown_80E2C48[0], 0, 0, 0x101);
             break;
         case 0x26:
-            if (FriendList_GetPtr() != 0)
+            if (FriendList_GetPtr() != NULL)
                 FriendList_Free();
             ResetUnusedInputStruct();
             ShowWindows(NULL, TRUE, TRUE);
diff --git a/src/m4a.c b/src/m4a.c
index a6ec3fc20..64eef566a 100644
--- a/src/m4a.c
+++ b/src/m4a.c
@@ -1,4 +1,5 @@
 #include "global.h"
+#include "m4a.h"
 #include "gba/m4a_internal.h"
 
 extern const u8 gCgb3Vol[];
@@ -7,7 +8,7 @@ IWRAM_DATA ALIGNED(4) char SoundMainRAM_Buffer[0x400] = {0};
 
 EWRAM_DATA struct MusicPlayerInfo gMPlayInfo_SE4 = {0};
 EWRAM_DATA struct MusicPlayerInfo gMPlayInfo_SE5 = {0};
-EWRAM_DATA struct MusicPlayerInfo gMPlayInfo_BGM = {0}; // BGM??
+EWRAM_DATA struct MusicPlayerInfo gMPlayInfo_BGM = {0};
 EWRAM_DATA struct MusicPlayerInfo gMPlayInfo_SE6 = {0};
 EWRAM_DATA struct MusicPlayerInfo gMPlayInfo_Fanfare = {0};
 EWRAM_DATA struct MusicPlayerInfo gMPlayInfo_SE1 = {0};
diff --git a/src/mailbox.c b/src/mailbox.c
index 6d991ceae..c5afd52e6 100644
--- a/src/mailbox.c
+++ b/src/mailbox.c
@@ -82,7 +82,7 @@ void CreateMailboxMenu(void);
 void CreateMailActionMenu(void);
 void CreateMailAcceptedStatusBox(u32);
 
-u32 sub_802DFB0(void)
+u8 sub_802DFB0(void)
 {
     gUnknown_203B304 = MemoryAlloc(sizeof(struct unkStruct_203B304), 8);
     gUnknown_203B304->menuAction1 = 0;
diff --git a/src/pelipper_board.c b/src/pelipper_board.c
index e3d3bbb36..94125eee8 100644
--- a/src/pelipper_board.c
+++ b/src/pelipper_board.c
@@ -79,14 +79,14 @@ static void sub_802EC10(void);
 static void CreatePelipperAcceptedStatusBox(u32);
 static void SetPelipperBoardState(u32);
 
-u32 sub_802E864(void)
+bool8 sub_802E864(void)
 {
     gPelipperBoard = MemoryAlloc(sizeof(struct unkStruct_203B308), 8);
     gPelipperBoard->menuAction1 = 0;
     gPelipperBoard->menuAction2 = 0;
     gPelipperBoard->unk4 = 0;
     SetPelipperBoardState(INITIALIZE_PELIPPER_BOARD);
-    return 1;
+    return TRUE;
 }
 
 u32 sub_802E890(void)
diff --git a/src/save.c b/src/save.c
index 81a732a6f..b3f541dff 100644
--- a/src/save.c
+++ b/src/save.c
@@ -15,6 +15,7 @@
 #include "adventure_save.h"
 #include "training_maze.h"
 #include "rescue_scenario.h"
+#include "code_800D090_1.h"
 
 // size: 0x800
 struct unk_struct
@@ -38,9 +39,6 @@ ALIGNED(4) static const char fill_save0[] = _("pksdir0");
 ALIGNED(4) static const char fill_save1[] = _("pksdir0");
 ALIGNED(4) static const char fill_save2[] = _("pksdir0");
 
-extern bool8 sub_800DAB0(u16, u8*, s32);
-extern bool8 sub_800DAB4(u16, u8*, s32);
-extern bool8 sub_800DAB8(void);
 extern u32 sub_80954CC(void* a, s32 b);
 extern u32 sub_8095624(u8 *, u32);
 extern u32 RestoreMailInfo(void* a, s32 b);
diff --git a/src/textbox.c b/src/textbox.c
index 07cee1211..433da7dfd 100644
--- a/src/textbox.c
+++ b/src/textbox.c
@@ -48,8 +48,11 @@
 #include "wonder_mail.h"
 #include "naming_screen.h"
 #include "dungeon_list_menu.h"
+#include "thank_you_wonder_mail.h"
 #include "game_options.h"
+#include "pelipper_board.h"
 #include "script_item.h"
+#include "mailbox.h"
 #include "structs/menu.h"
 #include "structs/str_file_system.h"
 #include "structs/str_mon_portrait.h"
@@ -139,9 +142,6 @@ u32 sub_802E90C();
 void sub_802E918();
 u32 sub_80282DC(u8 *r0);
 void sub_80282FC(void);
-extern u8 CreateThankYouMailPelipper(void);
-extern u8 sub_802E864(void);
-extern u8 sub_802DFB0(void);
 extern void CleanThankYouMailPelipper(void);
 extern void CleanHelperPelipper(void);
 extern void sub_802E06C(void);
diff --git a/src/thank_you_wonder_mail.c b/src/thank_you_wonder_mail.c
index 40b7731f9..9d8d72a20 100644
--- a/src/thank_you_wonder_mail.c
+++ b/src/thank_you_wonder_mail.c
@@ -25,6 +25,7 @@
 #include "wonder_mail_4.h"
 #include "wonder_mail_5.h"
 #include "naming_screen.h"
+#include "code_803C1B4.h"
 
 static EWRAM_INIT WonderMailStruct_203B2C4 *sUnknown_203B2C4 = {NULL};
 
@@ -216,14 +217,13 @@ extern void sub_802A850();
 extern void sub_8031E10();
 extern void SetThankYouMailMenuState(u32);
 extern u8 sub_800D588(void);
-extern u32 GetDungeonTeamRankPts(DungeonLocation *, u32);
 extern void sub_8031D70(u8, u32);
 
 extern void sub_8011C28(u32);
 extern u32 sub_8039068(u32, u8 *r1, unkStruct_203B480 *r0);
 
 
-u32 CreateThankYouMailPelipper(void)
+bool8 CreateThankYouMailPelipper(void)
 {
   char *monName;
   OpenedFile *faceFile;
@@ -270,7 +270,7 @@ u32 CreateThankYouMailPelipper(void)
     SetThankYouMailMenuState(THANK_YOU_MAIL_MAIN_MENU);
   }
   sUnknown_203B2C4->fallbackState = 0x2b;
-  return 1;
+  return TRUE;
 }
 
 u32 ThankYouMailPelipperCallback(void)
diff --git a/src/wonder_mail.c b/src/wonder_mail.c
index 1b2527b66..9f2a84130 100644
--- a/src/wonder_mail.c
+++ b/src/wonder_mail.c
@@ -40,7 +40,6 @@ extern void sub_8031E10();
 extern void sub_8031E00();
 extern void sub_8031E10(void);
 extern void sub_8031D70(u8, u32);
-extern u32 FriendList_GetPtr(void);
 extern void sub_8030F58(u32);
 extern void sub_8029B34(void);
 extern void sub_8029AD8(void);
@@ -454,7 +453,7 @@ void sub_8028348(void)
             CreateDialogueBoxAndPortrait(gUnknown_80DDCBC, 0, 0,0x101);
             break;
         case SELECT_HELPER_POKEMON:
-            if(FriendList_GetPtr() == 0)
+            if (FriendList_GetPtr() == NULL)
             {
                 ResetUnusedInputStruct();
                 ShowWindows(NULL, TRUE, TRUE);
diff --git a/src/wonder_mail_2.c b/src/wonder_mail_2.c
index 06a519edf..e9c7e81e8 100644
--- a/src/wonder_mail_2.c
+++ b/src/wonder_mail_2.c
@@ -19,6 +19,7 @@
 #include "string_format.h"
 #include "text_1.h"
 #include "ground_main.h"
+#include "code_803C1B4.h"
 
 struct unkStruct_203B2C8
 {
@@ -48,9 +49,6 @@ extern void sub_802B5B8(void);
 extern void sub_802B5FC(void);
 extern void sub_802B624(void);
 
-extern void sub_803C37C(DungeonLocation *, u32, u8 *);
-extern u32 GetDungeonTeamRankPts(DungeonLocation *, u32);
-
 ALIGNED(4) const char gRescueTeamNamePlaceholder[] = "????";
 
 ALIGNED(4) const char gUnknown_80DF9F8[] = _(