diff --git a/include/code_809447C.h b/include/code_809447C.h
index cfd1c94d5..08cbc077c 100644
--- a/include/code_809447C.h
+++ b/include/code_809447C.h
@@ -2,12 +2,12 @@
 #define GUARD_CODE_809447C_H
 
 // size: 0xC
-struct unkStruct_80928C0
+typedef struct unkStruct_80928C0
 {
     u32 unk0;
     s32 unk4;
     u8 unk8;
     u8 unk9;
-};
+} unkStruct_80928C0;
 
-#endif
\ No newline at end of file
+#endif // GUARD_CODE_809447C_H
\ No newline at end of file
diff --git a/include/code_8094F88.h b/include/code_8094F88.h
index 6706343a8..e4563104e 100644
--- a/include/code_8094F88.h
+++ b/include/code_8094F88.h
@@ -60,7 +60,7 @@ u32 *sub_8095108(void);
 unkStruct_203B48C *sub_8095110(void);
 void sub_8095118(void);
 s32 FindOpenMailSlot(void);
-bool8 sub_80951BC(unkStruct_203B480 *);
+bool8 sub_80951BC(unkStruct_203B480 *mail);
 bool8 sub_80951FC(unkStruct_203B480 *);
 unkStruct_203B480 * GetMailatIndex(u8);
 void DeleteMailAtIndex(u8);
@@ -76,4 +76,4 @@ s32 GetFirstIndexofMailType(u8);
 void sub_8095824(struct unkStruct_8094924 *, unkStruct_203B480 *);
 void sub_8095774(struct unkStruct_8094924 *, unkStruct_203B480 *);
 
-#endif
+#endif // GUARD_CODE_8094F88_H
\ No newline at end of file
diff --git a/include/code_80958E8.h b/include/code_80958E8.h
index f8cadd87c..965c9b7f0 100644
--- a/include/code_80958E8.h
+++ b/include/code_80958E8.h
@@ -4,28 +4,27 @@
 #include "wonder_mail.h"
 #include "constants/mailbox.h"
 
-struct subStruct_203B490
+// size: 0xC
+typedef struct subStruct_203B490
 {
-    // size: 0xC
-    DungeonLocation dungeon;
-    u32 seed;
+    /* 0x0 */ DungeonLocation dungeon;
+    /* 0x4 */ u32 seed;
     u32 unk8;
-};
- 
+} subStruct_203B490;
 
-struct unkStruct_203B490
+// size: 0x32C?
+typedef struct unkStruct_203B490
 {
-    // size: 0x330?
     /* 0x0 */ WonderMail mailboxSlots[NUM_MAILBOX_SLOTS];
     /* 0x50 */ WonderMail pelipperBoardJobs[MAX_ACCEPTED_JOBS];
     /* 0xF0 */ WonderMail jobSlots[MAX_ACCEPTED_JOBS];
     u8 unk190[0x28];
     u8 unk1B8[0x78];
-    struct subStruct_203B490 unk230[16];
-    u8 PKMNNewsReceived[NUM_POKEMON_NEWS];
+    subStruct_203B490 unk230[16];
+    /* 0x2F0 */ u8 PKMNNewsReceived[NUM_POKEMON_NEWS];
     bool8 unk328;
-};
+} unkStruct_203B490;
 
-extern struct unkStruct_203B490 *gUnknown_203B490;
+extern unkStruct_203B490 *gUnknown_203B490;
 
 #endif // GUARD_CODE_80958E8_H
\ No newline at end of file
diff --git a/include/code_80958E8_1.h b/include/code_80958E8_1.h
index 7e68cb418..144bd84dc 100644
--- a/include/code_80958E8_1.h
+++ b/include/code_80958E8_1.h
@@ -3,7 +3,7 @@
 
 #include "wonder_mail.h"
 
-s32 CountJobsinDungeon(u8);
-WonderMail *GetJobSlotInfo(u8);
+s32 CountJobsinDungeon(u8 dungeon);
+WonderMail *GetJobSlotInfo(u8 index);
 
 #endif // GUARD_CODE_80958E8_1_H
\ No newline at end of file
diff --git a/include/code_80972F4.h b/include/code_80972F4.h
index 7a018146e..c589b0e4b 100644
--- a/include/code_80972F4.h
+++ b/include/code_80972F4.h
@@ -2,18 +2,18 @@
 #define GUARD_CODE_80972F4_H
 
 // size: 0x8
-struct MissionText
+typedef struct MissionText
 {
     /* 0x0 */ u8 *text;
     u8 unk4;
     u8 unk5;
     u8 unk6;
     u8 unk7;
-};
+} MissionText;
 
 const u8 *GetCurrentMissionText(s16);
 // TODO: this should probably be bool8 but can't get a match just yet
-bool32 IsMazeCompleted(s16);
+bool32 IsMazeCompleted(s16 mazeIndex);
 
 bool8 sub_8097504(s16);
 const u8 *sub_80975DC(u32);
diff --git a/include/dungeon_pokemon_sprites.h b/include/dungeon_pokemon_sprites.h
index 27948e745..62da2adfe 100644
--- a/include/dungeon_pokemon_sprites.h
+++ b/include/dungeon_pokemon_sprites.h
@@ -3,37 +3,40 @@
 
 #include "position.h"
 
-DungeonPokemonStatusSprite
+// size: 0x8
+typedef struct DungeonPokemonStatusSprite
 {
-    u32 status;
-    u32 frame;
-};
+    /* 0x0 */ u32 status;
+    /* 0x4 */ u32 frame;
+} DungeonPokemonStatusSprite;
 
-DungeonPokemonSprite
+// size: 0x40
+typedef struct DungeonPokemonSprite
 {
-    /* 0x0000 */ u8 exists;
-    /* 0x0004 */ u32 id;
-    /* 0x0008 */ u16 species; // Or sprite ID?
-    /* 0x000A */ u16 unkA;
-    /* 0x000C */ u32 status;
-    /* 0x0010 */ u8 visible;
-    /* 0x0011 */ u8 unk11;
-    /* 0x0014 */ Position pos;
-    /* 0x0018 */ Position statusOffsets[2];
-    /* 0x0020 */ u32 unk20;
-    /* 0x0024 */ u32 unk24;
-    /* 0x0028 */ DungeonPokemonStatusSprite statusSprites[2];
-    /* 0x0038 */ u8 unk38;
-    /* 0x003C */ u16 unk3C;
-    /* 0x003E */ u16 unk3E;
-}
+    /* 0x0 */ u8 exists;
+    /* 0x4 */ u32 id;
+    /* 0x8 */ u16 species; // Or sprite ID?
+    /* 0xA */ u16 unkA;
+    /* 0xC */ u32 status;
+    /* 0x10 */ u8 visible;
+    /* 0x11 */ u8 unk11;
+    /* 0x14 */ Position pos;
+    /* 0x18 */ Position statusOffsets[2];
+    /* 0x20 */ u32 unk20;
+    /* 0x24 */ u32 unk24;
+    /* 0x28 */ DungeonPokemonStatusSprite statusSprites[2];
+    /* 0x38 */ u8 unk38;
+    /* 0x3C */ u16 unk3C;
+    /* 0x3E */ u16 unk3E;
+} DungeonPokemonSprite;
 
-DungeonPokemonSprites
+// size: 0x584
+typedef struct DungeonPokemonSprites
 {
-    u32 frame;
-    DungeonPokemonSprites sprites[22];
-};
+    /* 0x0 */ u32 frame;
+    /* 0x4 */ struct DungeonPokemonSprites sprites[22];
+} DungeonPokemonSprites;
 
 extern DungeonPokemonSprites *gDungeonPokemonSprites;
 
-#endif
+#endif // GUARD_DUNGEON_POKEMON_SPRITES_H
\ No newline at end of file
diff --git a/include/friend_area.h b/include/friend_area.h
index 7d23a5c51..bb34660ba 100644
--- a/include/friend_area.h
+++ b/include/friend_area.h
@@ -21,7 +21,7 @@ typedef struct unkStruct_8092638
 extern bool8 *gFriendAreas;
 
 bool8 *GetBoughtFriendAreas(void);
-const u8 *GetFriendAreaDescription(u8);
+const u8 *GetFriendAreaDescription(u8 index);
 const u8 *GetFriendAreaName(u8);
 s32 GetFriendAreaPrice(u8);
 bool8 GetFriendAreaStatus(u8);
diff --git a/include/gulpin_shop.h b/include/gulpin_shop.h
index 069dbb053..c108eab7c 100644
--- a/include/gulpin_shop.h
+++ b/include/gulpin_shop.h
@@ -36,7 +36,7 @@ typedef struct GulpinShopWork
     UnkTextStruct2 unk12C[4];
 } GulpinShopWork;
 
-bool8 CreateGulpinShop(s32, s16, Move *);
+bool8 CreateGulpinShop(s32 isAsleep, s16 pokeSpecies, Move *moves);
 void DestroyGulpinShop(void);
 bool8 GulpinIsNextMoveLinked(void);
 
diff --git a/include/gulpin_shop_801FB50.h b/include/gulpin_shop_801FB50.h
index a51a0c3e0..081235d48 100644
--- a/include/gulpin_shop_801FB50.h
+++ b/include/gulpin_shop_801FB50.h
@@ -8,7 +8,7 @@
 #include "text.h"
 
 // size: 0x1E0
-struct unkStruct_203B27C
+typedef struct unkStruct_203B27C
 {
     /* 0x0 */ bool32 isAsleep;
     /* 0x4 */ s32 state;
@@ -42,7 +42,7 @@ struct unkStruct_203B27C
     u8 unk17A;
     OpenedFile **unk17C;
     UnkTextStruct2 unk180[4];
-};
+} unkStruct_203B27C;
 
 bool8 sub_801FB50(u32);
 u32 sub_801FC40(void);
diff --git a/include/kangaskhan_storage1.h b/include/kangaskhan_storage1.h
index aa591fdba..4b2e9310e 100644
--- a/include/kangaskhan_storage1.h
+++ b/include/kangaskhan_storage1.h
@@ -54,7 +54,7 @@ struct KangaskhanStorageWork
     UnkTextStruct2 unkEC[4];
 };
 
-bool8 CreateKangaskhanStorage(u32);
+bool8 CreateKangaskhanStorage(u32 mode);
 void DeleteKangaskhanStorage(void);
 u32 KangaskhanStorageCallback(void);
 
diff --git a/include/kangaskhan_storage2.h b/include/kangaskhan_storage2.h
index 08f72664b..84c6ab0b1 100644
--- a/include/kangaskhan_storage2.h
+++ b/include/kangaskhan_storage2.h
@@ -6,7 +6,7 @@
 #include "text.h"
 
 // size: 0x150
-struct unkStruct_203B20C
+typedef struct unkStruct_203B20C
 {
     /* 0x0 */ u32 state;
     u8 unk4[4];
@@ -30,7 +30,7 @@ struct unkStruct_203B20C
     u32 unkE0;
     u8 fillE4[0xF0 - 0xE4];
     UnkTextStruct2 unkF0[4];
-};
+} unkStruct_203B20C;
 
 bool8 sub_8017E1C(void);
 u32 sub_8017E54(void);
diff --git a/include/kecleon_bros2.h b/include/kecleon_bros2.h
index bb49bd30f..0c72df25d 100644
--- a/include/kecleon_bros2.h
+++ b/include/kecleon_bros2.h
@@ -5,14 +5,14 @@
 #include "text.h"
 
 // size: 0xA0
-struct unkStruct_203B214
+typedef struct unkStruct_203B214
 {
     /* 0x0 */ MenuInputStruct input;
     u32 unk34;
     UnkTextStruct2 *unk38;
     UnkTextStruct2 unk3C[4];
     u8 unk9C[4];
-};
+} unkStruct_203B214;
 
 bool8 sub_8019E40(u32);
 u32 sub_8019EDC(u8);
diff --git a/include/kecleon_bros3.h b/include/kecleon_bros3.h
index 92b34579d..797e7d555 100644
--- a/include/kecleon_bros3.h
+++ b/include/kecleon_bros3.h
@@ -5,14 +5,14 @@
 #include "text.h"
 
 // size: 0xA0
-struct unkStruct_203B21C
+typedef struct unkStruct_203B21C
 {
     /* 0x0 */ MenuInputStruct input;
     u32 unk34;
     UnkTextStruct2 *unk38;
     UnkTextStruct2 unk3C[4];
     u8 unk9C[4];
-};
+} unkStruct_203B21C;
 
 u8 sub_801A20C(u32);
 u32 sub_801A2A8(u8);
diff --git a/include/kecleon_bros4.h b/include/kecleon_bros4.h
index 2cce6b984..fcd754231 100644
--- a/include/kecleon_bros4.h
+++ b/include/kecleon_bros4.h
@@ -6,7 +6,7 @@
 #include "text.h"
 
 // size: 0xF4
-struct unkStruct_203B224
+typedef struct unkStruct_203B224
 {
     u32 unk0;
     u32 unk4[INVENTORY_SIZE];
@@ -15,7 +15,7 @@ struct unkStruct_203B224
     UnkTextStruct2 *unk8C;
     UnkTextStruct2 unk90[4];
     u8 unkF0[4];
-};
+} unkStruct_203B224;
 
 bool8 sub_801A5D8(u32, s32, UnkTextStruct2_sub *, u32);
 u32 sub_801A6E8(bool8);
diff --git a/include/moves.h b/include/moves.h
index b557ac7f0..d1a80f606 100644
--- a/include/moves.h
+++ b/include/moves.h
@@ -76,8 +76,8 @@ bool8 UnlinkMovesAfter(s32, Move *);
 void UnSetMove(s32, Move *);
 
 u8 sub_809287C(Move *);
-void sub_80928A0(u8 *, Move *, const struct unkStruct_80928C0 *);
-void sub_80928C0(u8 *, Move *, const struct unkStruct_80928C0 *);
+void sub_80928A0(u8 *, Move *, const unkStruct_80928C0 *);
+void sub_80928C0(u8 *, Move *, const unkStruct_80928C0 *);
 void sub_8092AA8(Move *, u16);
 void sub_8092C84(u8 *, u16);
 s32 sub_8092DB8(Move *, s32);
diff --git a/include/music.h b/include/music.h
index 1238c1032..6298927e1 100644
--- a/include/music.h
+++ b/include/music.h
@@ -1,45 +1,6 @@
 #ifndef GUARD_MUSIC_H
 #define GUARD_MUSIC_H
 
-// size: 0x8. PMD keeps its own copy of music players for some reason
-struct PMDMusicPlayer
-{
-    u16 unk0;
-    u16 songIndex;
-    u16 volume;
-    bool8 isNotMaxVolume;
-};
-
-void InitMusic(void);
-
-void StopBGMusicVSync(void);
-void StartBGMusicVSync(void);
-bool8 IsValidSong(u32 songIndex);
-void StartNewBGM(u16 songIndex);
-bool8 IsBGSong(u32 songIndex);
-bool8 IsSoundEffect(u32 songIndex);
-bool8 IsFanfare(u32 songIndex);
-u16 GetMusicPlayerIndex(u16 songIndex);
-bool8 IsMusicPlayerPlaying(u16 songIndex);
-void StartNewBGM(u16 songIndex);
-void FadeInNewBGM(u16 songIndex, u16 speed);
-u16 GetCurrentBGSong(void);
-void QueueBGM(u16 songIndex);
-void StopBGM(void); // stops all BGM, fanfares and SE's
-void FadeOutBGM(u16 speed);
-void PlayFanfareSE(u16 songIndex, u16 volume);
-void StopFanfareSE(u16 songIndex);
-void FadeOutFanfareSE(u16 songIndex, u16 speed);
-bool8 IsFanfareSEPlaying(u16 songIndex);
-void SoundBiasReset(void);
-void SoundBiasSet(void);
-void UpdateSound(void);
-void SoundVSync(void);
-void nullsub_18(void);
-
-void nullsub_19(void);
-void nullsub_20(u16 songIndex);
-
 #define NUM_FANFARES 19
 #define FANFARE_START_INDEX 200
 
@@ -80,4 +41,34 @@ enum Fanfare_Player_State
     FANFARE_PLAYER_STATE_PLAYING = 3,
 };
 
+// size: 0x8. PMD keeps its own copy of music players for some reason
+typedef struct PMDMusicPlayer
+{
+    u16 unk0;
+    u16 songIndex;
+    u16 volume;
+    bool8 isNotMaxVolume;
+} PMDMusicPlayer;
+
+void FadeInNewBGM(u16 songIndex, u16 speed);
+void FadeOutBGM(u16 speed);
+void FadeOutFanfareSE(u16 songIndex, u16 speed);
+u16 GetCurrentBGSong(void);
+void InitMusic(void);
+bool8 IsFanfareSEPlaying(u16 songIndex);
+void nullsub_18(void);
+void PlayFanfareSE(u16 songIndex, u16 volume);
+void QueueBGM(u16 songIndex);
+void SoundVSync(void);
+void StartBGMusicVSync(void);
+void StartNewBGM(u16 songIndex);
+void StopBGM(void); // Stops all BGM, fanfares and SE's
+void StopBGMusicVSync(void);
+void StopFanfareSE(u16 songIndex);
+void UpdateSound(void);
+
+// libagbsyscall
+extern void SoundBiasReset(void);
+extern void SoundBiasSet(void);
+
 #endif //GUARD_MUSIC_H
\ No newline at end of file
diff --git a/include/pokemon.h b/include/pokemon.h
index 24fe27145..bcd909324 100644
--- a/include/pokemon.h
+++ b/include/pokemon.h
@@ -202,7 +202,7 @@ void CopyMonsterNametoBuffer(u8 * buffer, s16 index);
 void CopyYellowMonsterNametoBuffer(u8 *buffer, s16 index);
 void PrintColoredPokeNameToBuffer(u8 *buffer, PokemonStruct1 *pokemon, s32 colorNum);
 void sub_808D930(u8 *buffer, s32 index);
-void sub_808D9DC(u8 *, PokemonStruct2 *, s32);
+void sub_808D9DC(u8 *buffer, PokemonStruct2 *, s32 colorNum);
 void sub_808DA0C(u8 *, PokemonStruct2 *);
 void PeekPokemonItem(s16 index_, BulkItem* item);
 void GivePokemonItem(s16 index_, BulkItem* item);
diff --git a/include/save.h b/include/save.h
index 5993310e1..91c11b2c3 100644
--- a/include/save.h
+++ b/include/save.h
@@ -53,7 +53,7 @@ struct UnkStruct_203B184 {
     /* 0xC */ unkStruct_203B484 *unkC;
     /* 0x10 */ u32 *unk10;
     /* 0x14 */ unkStruct_203B48C *unk14;
-    /* 0x18 */ struct unkStruct_203B490 *mailInfo;
+    /* 0x18 */ unkStruct_203B490 *mailInfo;
     /* 0x1C */ struct RescueTeamData *RescueTeamInfo;
     /* 0x20 */ struct unkStruct_203B494 *unk20;
     /* 0x24 */ struct ExclusivePokemonData *ExclusivePokemon;
diff --git a/include/save_read.h b/include/save_read.h
index 4d237bde1..f32d454a1 100644
--- a/include/save_read.h
+++ b/include/save_read.h
@@ -2,11 +2,11 @@
 #define GUARD_SAVE_READ_H
 
 // size: 0x8
-struct SavePakRead
+typedef struct SavePakRead
 {
     /* 0x0 */ u32 state;
     /* 0x4 */ u32 readStatus;
-};
+} SavePakRead;
 
 void PrepareSavePakRead(void);
 bool8 ReadSavePak(void);
diff --git a/include/wigglytuff_shop.h b/include/wigglytuff_shop.h
index 661306fd8..39f6372b0 100644
--- a/include/wigglytuff_shop.h
+++ b/include/wigglytuff_shop.h
@@ -5,34 +5,6 @@
 #include "menu.h"
 #include "text.h"
 
-// size: 0x138
-typedef struct WigglytuffShop
-{
-    bool32 isAsleep;
-    s32 state;
-    s32 fallbackState;
-    s32 friendAreaPrice;
-    u8 chosenFriendArea;
-    s16 chosenSpecies;
-    u32 menuAction1;
-    u32 menuAction2;
-    MenuItem unk1C[8];
-    u16 unk5C[0x8];
-    MenuStruct unk6C;
-    /* 0xBC */ OpenedFile *faceFile;
-    /* 0xC0 */ u8 *faceData;
-    u16 unkC4;
-    u16 unkC6;
-    u8 unkC8;
-    u8 unkC9;
-    u8 unkCA;
-    u8 fillCB;
-    OpenedFile **unkCC;
-    UnkTextStruct2 unkD0[4];
-    u32 unk130;
-    u32 unk134;
-} WigglytuffShop;
-
 enum WigglytuffStates
 {
     WIGGLYTUFF_INIT = 0,
@@ -66,8 +38,36 @@ enum WigglytuffStates
     WIGGLYTUFF_CHECK_LEGENDARY = 28,
 };
 
-bool8 sub_80211AC(u32, u32);
-bool8 sub_8021774(u8, bool8, s32);
+// size: 0x138
+typedef struct WigglytuffShop
+{
+    bool32 isAsleep;
+    s32 state;
+    s32 fallbackState;
+    s32 friendAreaPrice;
+    u8 chosenFriendArea;
+    s16 chosenSpecies;
+    u32 menuAction1;
+    u32 menuAction2;
+    MenuItem unk1C[8];
+    u16 unk5C[0x8];
+    MenuStruct unk6C;
+    /* 0xBC */ OpenedFile *faceFile;
+    /* 0xC0 */ u8 *faceData;
+    u16 unkC4;
+    u16 unkC6;
+    u8 unkC8;
+    u8 unkC9;
+    u8 unkCA;
+    u8 fillCB;
+    OpenedFile **unkCC;
+    UnkTextStruct2 unkD0[4];
+    u32 unk130;
+    u32 unk134;
+} WigglytuffShop;
+
+bool8 sub_80211AC(u32 mode, u32);
+bool8 sub_8021774(u8 friendArea, bool8, s32);
 u32 sub_8021274(bool8);
 u8 sub_802132C(void);
 void sub_8021354(bool8);
diff --git a/src/code_80958E8.c b/src/code_80958E8.c
index 00805ab02..ee0953b18 100644
--- a/src/code_80958E8.c
+++ b/src/code_80958E8.c
@@ -19,17 +19,18 @@ extern void ResetPelipperBoardSlot(u8);
 extern void ResetJobSlot(u8);
 extern bool8 ValidateWonderMail(WonderMail *);
 
-EWRAM_DATA_2 struct unkStruct_203B490 *gUnknown_203B490 = {0};
-EWRAM_DATA struct unkStruct_203B490 gUnknown_2039448 = {0};
+static EWRAM_DATA unkStruct_203B490 sUnknown_2039448 = {0};
+
+EWRAM_DATA_2 unkStruct_203B490 *gUnknown_203B490 = {0};
 
 void LoadMailInfo(void)
 {
-    gUnknown_203B490 = &gUnknown_2039448;
+    gUnknown_203B490 = &sUnknown_2039448;
 }
 
-struct unkStruct_203B490 *GetMailInfo(void)
+unkStruct_203B490 *GetMailInfo(void)
 {
-    return &gUnknown_2039448;
+    return &sUnknown_2039448;
 }
 
 void InitializeMailJobsNews(void)
diff --git a/src/code_80972F4.c b/src/code_80972F4.c
index 037b21ede..d9d83e2d1 100644
--- a/src/code_80972F4.c
+++ b/src/code_80972F4.c
@@ -9,7 +9,7 @@
 #include "code_80A26CC.h"
 #include "code_80972F4.h"
 
-extern struct MissionText gStoryMissionText[];
+extern MissionText gStoryMissionText[];
 extern const char gFinalScenarioText[];
 extern const char gMeetNinetalesText[];
 extern const char gAvoidCaptureText[];
@@ -32,7 +32,7 @@ bool8 sub_8096F50(WonderMail *mail)
 {
     s32 index;
     s32 temp2;
-    struct subStruct_203B490 *temp;
+    subStruct_203B490 *temp;
 
     temp2 = sub_8096EB0(mail);
 
@@ -276,7 +276,7 @@ void sub_8097418(s16 index,u32 param_2)
   u8 param_2_u8 = param_2;
   if (index_s32 != 0xd) {
     if ((param_2_u8 != 0) && (sub_800199C(0,0x2c,index_s32,0), index_s32 < 0x1f)) {
-      struct MissionText *mt = &gStoryMissionText[index_s32];
+      MissionText *mt = &gStoryMissionText[index_s32];
       if (mt->unk4 != 0xFF) {
         sub_8097FA8(mt->unk4);
       }
@@ -320,7 +320,7 @@ const u8 *GetCurrentMissionText(s16 index)
 {
     if(index < 0x1F)
     {
-        struct MissionText *mt = &gStoryMissionText[index];
+        MissionText *mt = &gStoryMissionText[index];
         return mt->text;
     }
     else
diff --git a/src/data/post_office_guide1.h b/src/data/post_office_guide1.h
index e48a03c7d..0db013b7f 100644
--- a/src/data/post_office_guide1.h
+++ b/src/data/post_office_guide1.h
@@ -21,8 +21,6 @@ enum PostOfficeMenuActions
     SEND_THANK_YOU_MAIL
 };
 
-//
-
 static const u8 sPostOffice[];
 static const u8 sBulletinBoard[];
 static const u8 sDelivery[];
@@ -45,8 +43,6 @@ ALIGNED(4) static const u8 sDelivery[] = _("Delivery");
 ALIGNED(4) static const u8 sBulletinBoard[] = _("Bulletin Board");
 ALIGNED(4) static const u8 sPostOffice[] = _("Post Office");
 
-//
-
 static const u8 sFriendRescueInfo[];
 static const u8 sGoRescue[];
 static const u8 sGetHelp[];
@@ -69,8 +65,6 @@ ALIGNED(4) static const u8 sGetHelp[] = _("{COLOR_1 YELLOW}Get help{END_COLOR_TE
 ALIGNED(4) static const u8 sGoRescue[] = _("{COLOR_1 YELLOW}Go rescue{END_COLOR_TEXT_1} ");
 ALIGNED(4) static const u8 sFriendRescueInfo[] = _("Friend Rescue Info");
 
-//
-
 static const MenuItem sPostOfficeHelpGoRescueMenu[] =
 {
     {"Rescue Procedures", RESCUE_PROCEDURES},
@@ -82,8 +76,6 @@ static const MenuItem sPostOfficeHelpGoRescueMenu[] =
     {NULL, EXIT}
 };
 
-//
-
 static const MenuItem sPostOfficeHelpGetHelpMenu[] =
 {
     {"Getting Help", GETTING_HELP},
@@ -94,8 +86,6 @@ static const MenuItem sPostOfficeHelpGetHelpMenu[] =
     {NULL, EXIT}
 };
 
-//
-
 ALIGNED(4) static const u8 sWhatdYouWantToKnow[] =
     _(" So{COMMA} what{APOSTROPHE}d you want to\n"
     "know?");
diff --git a/src/gulpin_shop_801FB50.c b/src/gulpin_shop_801FB50.c
index 15c311dfd..68cd83752 100644
--- a/src/gulpin_shop_801FB50.c
+++ b/src/gulpin_shop_801FB50.c
@@ -16,7 +16,7 @@
 #include "text1.h"
 #include "text2.h"
 
-EWRAM_DATA_2 struct unkStruct_203B27C *gUnknown_203B27C = {0};
+EWRAM_DATA_2 unkStruct_203B27C *gUnknown_203B27C = {0};
 
 extern u8 gAvailablePokemonNames[]; // 202DF98
 extern u8 gUnknown_202DFE8[];
@@ -72,7 +72,7 @@ bool8 sub_801FB50(u32 mode)
 
     ResetUnusedInputStruct();
     sub_800641C(NULL, TRUE, TRUE);
-    gUnknown_203B27C = MemoryAlloc(sizeof(struct unkStruct_203B27C), 0x8);
+    gUnknown_203B27C = MemoryAlloc(sizeof(unkStruct_203B27C), 0x8);
     gUnknown_203B27C->menuAction2 = 0;
     gUnknown_203B27C->menuAction3 = 0;
     gUnknown_203B27C->menuAction4 = 0;
diff --git a/src/kangaskhan_storage2.c b/src/kangaskhan_storage2.c
index dc18ff9cf..075eb2558 100644
--- a/src/kangaskhan_storage2.c
+++ b/src/kangaskhan_storage2.c
@@ -10,7 +10,7 @@
 #include "text1.h"
 #include "text2.h"
 
-EWRAM_DATA_2 struct unkStruct_203B20C *gUnknown_203B20C = {0};
+EWRAM_DATA_2 unkStruct_203B20C *gUnknown_203B20C = {0};
 
 extern const u8 *gUnknown_80D4934[];
 extern const u8 *gUnknown_80D4958[];
@@ -39,7 +39,7 @@ bool8 sub_8017E1C(void)
 {
     ResetUnusedInputStruct();
     sub_800641C(NULL, TRUE, TRUE);
-    gUnknown_203B20C = MemoryAlloc(sizeof(struct unkStruct_203B20C), 8);
+    gUnknown_203B20C = MemoryAlloc(sizeof(unkStruct_203B20C), 8);
     gUnknown_203B20C->menuAction1 = 0;
     gUnknown_203B20C->menuAction2 = 0;
     gUnknown_203B20C->menuAction3 = 0;
diff --git a/src/kecleon_bros2.c b/src/kecleon_bros2.c
index fca0771cd..ae50a2a8d 100644
--- a/src/kecleon_bros2.c
+++ b/src/kecleon_bros2.c
@@ -9,7 +9,7 @@
 #include "text1.h"
 #include "text2.h"
 
-static EWRAM_DATA_2 struct unkStruct_203B214 *gUnknown_203B214 = {0};
+static EWRAM_DATA_2 unkStruct_203B214 *gUnknown_203B214 = {0};
 static EWRAM_DATA_2 u16 gUnknown_203B218 = {0};
 
 #include "data/kecleon_bros2.h"
@@ -21,7 +21,7 @@ bool8 sub_8019E40(u32 r0)
     if (CountKecleonShopItems() == 0)
         return FALSE;
 
-    gUnknown_203B214 = MemoryAlloc(sizeof(struct unkStruct_203B214), 8);
+    gUnknown_203B214 = MemoryAlloc(sizeof(unkStruct_203B214), 8);
     gUnknown_203B214->unk34 = r0;
     gUnknown_203B214->unk38 = &gUnknown_203B214->unk3C[gUnknown_203B214->unk34];
     sub_8006518(gUnknown_203B214->unk3C);
diff --git a/src/kecleon_bros3.c b/src/kecleon_bros3.c
index 9108d3ce5..633619d52 100644
--- a/src/kecleon_bros3.c
+++ b/src/kecleon_bros3.c
@@ -9,7 +9,7 @@
 #include "text1.h"
 #include "text2.h"
 
-static EWRAM_DATA_2 struct unkStruct_203B21C *gUnknown_203B21C = {0};
+static EWRAM_DATA_2 unkStruct_203B21C *gUnknown_203B21C = {0};
 static EWRAM_DATA_2 u16 gUnknown_203B220 = {0};
 
 #include "data/kecleon_bros3.h"
@@ -21,7 +21,7 @@ u8 sub_801A20C(u32 r0)
     if (CountKecleonWareItems() == 0)
         return 0;
 
-    gUnknown_203B21C = MemoryAlloc(sizeof(struct unkStruct_203B21C), 8);
+    gUnknown_203B21C = MemoryAlloc(sizeof(unkStruct_203B21C), 8);
     gUnknown_203B21C->unk34 = r0;
     gUnknown_203B21C->unk38 = &gUnknown_203B21C->unk3C[gUnknown_203B21C->unk34];
     sub_8006518(gUnknown_203B21C->unk3C);
diff --git a/src/kecleon_bros4.c b/src/kecleon_bros4.c
index bba0e2a4d..eefd235df 100644
--- a/src/kecleon_bros4.c
+++ b/src/kecleon_bros4.c
@@ -13,7 +13,7 @@
 
 extern u8 gUnknown_202DE58[];
 
-static EWRAM_DATA_2 struct unkStruct_203B224 *gUnknown_203B224 = {0};
+static EWRAM_DATA_2 unkStruct_203B224 *gUnknown_203B224 = {0};
 static EWRAM_DATA_2 u16 gUnknown_203B228 = {0};
 static EWRAM_DATA_2 u16 gUnknown_203B22A = {0};
 
@@ -30,7 +30,7 @@ bool8 sub_801A5D8(u32 param_1, s32 param_2, UnkTextStruct2_sub *param_3, u32 par
         return FALSE;
 
     if (gUnknown_203B224 == NULL)
-        gUnknown_203B224 = MemoryAlloc(sizeof(struct unkStruct_203B224), 8);
+        gUnknown_203B224 = MemoryAlloc(sizeof(unkStruct_203B224), 8);
 
     gUnknown_203B224->unk0 = param_1;
     FillInventoryGaps();
@@ -425,7 +425,7 @@ static void SortInventoryItems(void)
     }
 }
 
-UNUSED static struct unkStruct_203B224 *sub_801AF98(void)
+UNUSED static unkStruct_203B224 *sub_801AF98(void)
 {
     return gUnknown_203B224;
 }
\ No newline at end of file
diff --git a/src/mailbox_8095F8C.c b/src/mailbox_8095F8C.c
index 5e3ff99f5..4f4996b81 100644
--- a/src/mailbox_8095F8C.c
+++ b/src/mailbox_8095F8C.c
@@ -2,7 +2,7 @@
 #include "wonder_mail.h"
 #include "code_80958E8.h"
 
-extern struct unkStruct_203B490 *gUnknown_203B490;
+extern unkStruct_203B490 *gUnknown_203B490;
 
 bool8 IsMailSlotEmpty(u8);
 void ResetMailboxSlot(u8);
diff --git a/src/moves.c b/src/moves.c
index 5dbcee221..525fee219 100644
--- a/src/moves.c
+++ b/src/moves.c
@@ -18,7 +18,7 @@ extern u32 gUnknown_202DE30;
 extern u8 gAvailablePokemonNames[]; // 202DF98
 
 // data_8107010.s
-extern const struct unkStruct_80928C0 gUnknown_81098C4;
+extern const unkStruct_80928C0 gUnknown_81098C4;
 extern const u8 gUnknown_81098D0[];
 extern const u8 gUnknown_81098DC[];
 extern const u8 gUnknown_81098E0[];
@@ -72,14 +72,14 @@ u8 sub_809287C(Move *move)
     return 50;
 }
 
-void sub_80928A0(u8 *buffer, Move *move, const struct unkStruct_80928C0 *a2)
+void sub_80928A0(u8 *buffer, Move *move, const unkStruct_80928C0 *a2)
 {
     Move stack;
     CopyAndResetMove(&stack, move);
     sub_80928C0(buffer, &stack, a2);
 }
 
-void sub_80928C0(u8 *buffer, Move *move, const struct unkStruct_80928C0 *param_3)
+void sub_80928C0(u8 *buffer, Move *move, const unkStruct_80928C0 *param_3)
 {
     u32 uVar2;
     u32 basePP;
diff --git a/src/music.c b/src/music.c
index 24b1b209c..27654f880 100644
--- a/src/music.c
+++ b/src/music.c
@@ -4,24 +4,32 @@
 #include "main.h"
 #include "music.h"
 
-EWRAM_DATA u16 gBGMusicPlayerState = {0};
-EWRAM_DATA u16 gCurrentBGSong = {0};
-EWRAM_DATA u16 gQueuedBGSong = {0};
-EWRAM_DATA u16 gCurrentFanfareSong = {0};
-EWRAM_DATA u16 gFanfareMusicPlayerState = {0};
-EWRAM_DATA u16 gMusicTransitionCounter = {0};
-EWRAM_DATA bool8 gRestartBGM = {0};
+static EWRAM_DATA u16 sBGMusicPlayerstate = {0};
+static EWRAM_DATA u16 sCurrentBGSong = {0};
+static EWRAM_DATA u16 sQueuedBGSong = {0};
+static EWRAM_DATA u16 sCurrentFanfareSong = {0};
+static EWRAM_DATA u16 sFanfareMusicPlayerState = {0};
+static EWRAM_DATA u16 sMusicTransitionCounter = {0};
+static EWRAM_DATA bool8 sRestartBGM = {0};
 
-IWRAM_DATA struct PMDMusicPlayer gBGMusicPlayers[NUM_BG_PLAYERS] = {0};
-IWRAM_DATA struct PMDMusicPlayer gSEMusicPlayers[NUM_SE_PLAYERS] = {0};
+static IWRAM_DATA PMDMusicPlayer sBGMusicPlayers[NUM_BG_PLAYERS] = {0};
+static IWRAM_DATA PMDMusicPlayer sSEMusicPlayers[NUM_SE_PLAYERS] = {0};
 
-void nullsub_21(u16);
+static u16 GetMusicPlayerIndex(u16 songIndex);
+static bool8 IsBGSong(u32 songIndex);
+static bool8 IsFanfare(u32 songIndex);
+static bool8 IsMusicPlayerPlaying(u16 playerIndex);
+static bool8 IsSoundEffect(u32 songIndex);
+
+static void nullsub_19(void);
+static void nullsub_20(u16 songIndex);
+static void nullsub_21(u16 songIndex);
 
 void InitMusic(void)
 {
     s32 playerIndex;
 
-    struct PMDMusicPlayer *musicPlayer;
+    PMDMusicPlayer *musicPlayer;
 
     DmaStop(0);
     DmaStop(1);
@@ -30,25 +38,25 @@ void InitMusic(void)
 
     m4aSoundInit();
 
-    gBGMusicPlayerState = 0;
-    gCurrentBGSong = STOP_BGM;
-    gQueuedBGSong = STOP_BGM;
-    gCurrentFanfareSong = STOP_SOUND_EFFECT;
-    gFanfareMusicPlayerState = 0;
-    gMusicTransitionCounter = 0;
-    gRestartBGM = FALSE;
+    sBGMusicPlayerstate = 0;
+    sCurrentBGSong = STOP_BGM;
+    sQueuedBGSong = STOP_BGM;
+    sCurrentFanfareSong = STOP_SOUND_EFFECT;
+    sFanfareMusicPlayerState = 0;
+    sMusicTransitionCounter = 0;
+    sRestartBGM = FALSE;
 
-    for(playerIndex = INDEX_BGM, musicPlayer = &gBGMusicPlayers[0]; playerIndex < INDEX_SE6 + 1; playerIndex++, musicPlayer++)
-    {
+    for (playerIndex = INDEX_BGM, musicPlayer = &sBGMusicPlayers[0]; playerIndex < INDEX_SE6 + 1; playerIndex++, musicPlayer++) {
         musicPlayer->unk0 = 0;
         musicPlayer->songIndex = STOP_SOUND_EFFECT;
         musicPlayer->volume = 0;
         musicPlayer->isNotMaxVolume = FALSE;
     }
+
     nullsub_19();
 }
 
-void StopAllMusic(void)
+UNUSED static void StopAllMusic(void)
 {
     StopBGM();
     StopFanfareSE(STOP_FANFARE);
@@ -59,30 +67,28 @@ void StartNewBGM(u16 songIndex)
 {
     bool8 interrupt_flag;
 
-    if(!IsBGSong(songIndex))
+    if (!IsBGSong(songIndex))
         return;
-    if(songIndex == STOP_BGM)
+    if (songIndex == STOP_BGM)
         return;
-    if(songIndex == gCurrentBGSong)
-    {
-        if((u16)(gBGMusicPlayerState - 1) <= 1)
+    if (songIndex == sCurrentBGSong) {
+        if ((u16)(sBGMusicPlayerstate - 1) <= 1)
             return;
     }
-    if(GetMusicPlayerIndex(songIndex) != INDEX_BGM)
-    {
+    if (GetMusicPlayerIndex(songIndex) != INDEX_BGM) {
         nullsub_20(songIndex);
         return;
     }
-    interrupt_flag = DisableInterrupts();
-    gCurrentBGSong = songIndex;
-    gRestartBGM = TRUE;
 
-    if(gFanfareMusicPlayerState == 0)
-    {
-        gBGMusicPlayerState = BG_PLAYER_STATE_PLAYING;
+    interrupt_flag = DisableInterrupts();
+    sCurrentBGSong = songIndex;
+    sRestartBGM = TRUE;
+
+    if (sFanfareMusicPlayerState == 0) {
+        sBGMusicPlayerstate = BG_PLAYER_STATE_PLAYING;
         m4aSongNumStart(songIndex);
     }
-    if(interrupt_flag)
+    if (interrupt_flag)
         EnableInterrupts();
 }
 
@@ -90,70 +96,63 @@ void FadeInNewBGM(u16 songIndex, u16 speed)
 {
     bool8 interrupt_flag;
 
-    if(!IsBGSong(songIndex))
+    if (!IsBGSong(songIndex))
         return;
-    if(songIndex == STOP_BGM)
+    if (songIndex == STOP_BGM)
         return;
-    if(songIndex == gCurrentBGSong)
-    {
-        if((u16)(gBGMusicPlayerState - 1) <= 1)
+    if (songIndex == sCurrentBGSong) {
+        if ((u16)(sBGMusicPlayerstate - 1) <= 1)
             return;
     }
 
-    if((speed > 256))
-    {
+    if (speed > 256)
         speed = 16;
-
-    }
-    else
-    {
-        if((speed >>= 4) == 0)
-        {
+    else {
+        speed >>= 4;
+        if (speed == 0)
             speed = 1;
-        }
     }
 
     interrupt_flag = DisableInterrupts();
-    gCurrentBGSong = songIndex;
-    gRestartBGM = TRUE;
+    sCurrentBGSong = songIndex;
+    sRestartBGM = TRUE;
 
-    if(gFanfareMusicPlayerState == 0)
-    {
-        gBGMusicPlayerState = BG_PLAYER_STATE_PLAYING;
+    if (sFanfareMusicPlayerState == 0) {
+        sBGMusicPlayerstate = BG_PLAYER_STATE_PLAYING;
         m4aSongNumStart(songIndex);
         m4aMPlayImmInit(&gMPlayInfo_BGM);
         m4aMPlayVolumeControl(&gMPlayInfo_BGM, 0xFF, 0);
         m4aSongNumStop(songIndex);
         m4aMPlayFadeIn(&gMPlayInfo_BGM, speed);
     }
-    if(interrupt_flag)
+
+    if (interrupt_flag)
         EnableInterrupts();
 }
 
 void QueueBGM(u16 songIndex)
 {
-    if(gCurrentBGSong == STOP_BGM)
-    {
+    if (sCurrentBGSong == STOP_BGM) {
         StartNewBGM(songIndex);
-        gQueuedBGSong = STOP_BGM;
+        sQueuedBGSong = STOP_BGM;
     }
     else
-        gQueuedBGSong = songIndex;
+        sQueuedBGSong = songIndex;
 }
 
 void StopBGM(void)
 {
     bool8 interrupt_flag = DisableInterrupts();
-    if(gFanfareMusicPlayerState == 0)
-    {
-        if(gCurrentBGSong != STOP_BGM)
-        {
+
+    if (sFanfareMusicPlayerState == 0) {
+        if (sCurrentBGSong != STOP_BGM)
             m4aMPlayStop(&gMPlayInfo_BGM);
-        }
     }
-    gCurrentBGSong = STOP_BGM;
-    gQueuedBGSong = STOP_BGM;
-    if(interrupt_flag)
+
+    sCurrentBGSong = STOP_BGM;
+    sQueuedBGSong = STOP_BGM;
+
+    if (interrupt_flag)
         EnableInterrupts();
 }
 
@@ -161,225 +160,208 @@ void FadeOutBGM(u16 speed)
 {
     bool8 interrupt_flag;
 
-    if(speed > ((0x80 << 17) / 65536))
-    {
+// TODO: int16 memes
+    if (speed > (0x80 << 17) / 65536)
         speed = 16;
-    }
-    else
-    {
-        if((speed >>= 4) == 0)
-        {
+    else {
+        speed >>= 4;
+        if (speed == 0)
             speed = 1;
-        }
     }
+
     interrupt_flag = DisableInterrupts();
-    if(gFanfareMusicPlayerState == 0)
-    {
-        if(gCurrentBGSong != STOP_BGM)
-        {
-            if(gBGMusicPlayerState == 2)
-            {
-                gBGMusicPlayerState = 3;
+
+    if (sFanfareMusicPlayerState == 0) {
+        if (sCurrentBGSong != STOP_BGM) {
+            if (sBGMusicPlayerstate == 2) {
+                sBGMusicPlayerstate = 3;
                 m4aMPlayFadeOut(&gMPlayInfo_BGM, speed);
             }
-            else
-            {
-                gCurrentBGSong = STOP_BGM;
+            else {
+                sCurrentBGSong = STOP_BGM;
                 m4aMPlayStop(&gMPlayInfo_BGM);
             }
         }
     }
     else
-    {
-        gCurrentBGSong = STOP_BGM;
-    }
-    gQueuedBGSong = STOP_BGM;
-    if(interrupt_flag)
+        sCurrentBGSong = STOP_BGM;
+
+    sQueuedBGSong = STOP_BGM;
+
+    if (interrupt_flag)
         EnableInterrupts();
 }
 
 u16 GetCurrentBGSong(void)
 {
-    return gCurrentBGSong;
+    return sCurrentBGSong;
 }
 
 void PlayFanfareSE(u16 songIndex, u16 volume)
 {
-  bool8 interrupt_flag;
-  bool8 interrupt_flag2;
-  u16 playerIndex;
-  struct PMDMusicPlayer *musicPlayer;
+    bool8 interrupt_flag;
+    bool8 interrupt_flag2;
+    u16 playerIndex;
+    PMDMusicPlayer *musicPlayer;
 
-  if (songIndex == STOP_SOUND_EFFECT)
-    return;
-  if (volume > MAX_VOLUME)
-    volume = MAX_VOLUME;
+    if (songIndex == STOP_SOUND_EFFECT)
+        return;
+    if (volume > MAX_VOLUME)
+        volume = MAX_VOLUME;
 
-  if (IsFanfare(songIndex)) 
-  {
-    if (GetMusicPlayerIndex(songIndex) == INDEX_FANFARE) {
-      interrupt_flag = DisableInterrupts();
-      gCurrentFanfareSong = songIndex;
-      if(gFanfareMusicPlayerState == 0)
-      {
-        if (gCurrentBGSong != STOP_BGM) 
-        {
-            if ((u16)(gBGMusicPlayerState - 1) < 2)
-            {
-                gFanfareMusicPlayerState = 1;
-                gMusicTransitionCounter = 16;
-                gRestartBGM = FALSE;
-                m4aMPlayFadeOutTemporarily(&gMPlayInfo_BGM, 1);
+    if (IsFanfare(songIndex)) {
+        if (GetMusicPlayerIndex(songIndex) == INDEX_FANFARE) {
+            interrupt_flag = DisableInterrupts();
+            sCurrentFanfareSong = songIndex;
+            if (sFanfareMusicPlayerState == 0) {
+                if (sCurrentBGSong != STOP_BGM) {
+                    if ((u16)(sBGMusicPlayerstate - 1) < 2) {
+                        sFanfareMusicPlayerState = 1;
+                        sMusicTransitionCounter = 16;
+                        sRestartBGM = FALSE;
+                        m4aMPlayFadeOutTemporarily(&gMPlayInfo_BGM, 1);
+                    }
+                    else if (sBGMusicPlayerstate == 3)
+                        sFanfareMusicPlayerState = 2;
+                    else {
+                        sFanfareMusicPlayerState = FANFARE_PLAYER_STATE_PLAYING;
+                        m4aMPlayStop(&gMPlayInfo_BGM);
+                        m4aSongNumStart(sCurrentFanfareSong);
+                    }
+                }
+                else {
+                    sFanfareMusicPlayerState = FANFARE_PLAYER_STATE_PLAYING;
+                    m4aMPlayStop(&gMPlayInfo_BGM);
+                    m4aSongNumStart(sCurrentFanfareSong);
+                }
             }
-            else if (gBGMusicPlayerState == 3)
-                gFanfareMusicPlayerState = 2;
-            else
-            {
-                gFanfareMusicPlayerState = FANFARE_PLAYER_STATE_PLAYING;
-                m4aMPlayStop(&gMPlayInfo_BGM);
-                m4aSongNumStart(gCurrentFanfareSong);
+            else {
+                if (1 < (u16)(sFanfareMusicPlayerState - 1)) {
+                    m4aMPlayStop(&gMPlayInfo_BGM);
+                    m4aSongNumStart(sCurrentFanfareSong);
+                    sFanfareMusicPlayerState = FANFARE_PLAYER_STATE_PLAYING;
+                }
             }
+
+            switch (sCurrentBGSong) {
+                case MUS_RAYQUAZAS_DOMAIN:
+                case MUS_FRIEND_AREA_STRATOS_LOOKOUT:
+                case MUS_FRIEND_AREA_RAINBOW_PEAK:
+                case MUS_DREAM_EATER:
+                case MUS_FRIEND_AREA_DEEPSEA_CURRENT:
+                case MUS_FRIEND_AREA_SEAFLOOR_CAVE:
+                case MUS_FRIEND_AREA_VOLCANIC_PIT:
+                case MUS_FRIEND_AREA_CRYPTIC_CAVE:
+                case MUS_THE_OTHER_SIDE:
+                case MUS_THE_MOUNTAIN_OF_FIRE:
+                case MUS_FRIEND_AREA_LEGENDARY_ISLAND:
+                case MUS_FRIEND_AREA_SOUTHERN_ISLAND:
+                case MUS_FRIEND_AREA_ENCLOSED_ISLAND:
+                case MUS_FRIEND_AREA_FINAL_ISLAND:
+                case MUS_FRIEND_AREA_HEALING_FOREST:
+                    sRestartBGM = TRUE;
+                    break;
+                default:
+                    break;
+            }
+
+            if (interrupt_flag)
+                EnableInterrupts();
         }
+        else
+            nullsub_20(songIndex);
+    }
+    else {
+        if (!IsSoundEffect(songIndex))
+            return;
+
+        playerIndex = GetMusicPlayerIndex(songIndex);
+        musicPlayer = &sBGMusicPlayers[playerIndex]; // need to load this before comparison to match
+
+        if (playerIndex < INDEX_SE1)
+            nullsub_20(songIndex);
         else
         {
-            gFanfareMusicPlayerState = FANFARE_PLAYER_STATE_PLAYING;
-            m4aMPlayStop(&gMPlayInfo_BGM);
-            m4aSongNumStart(gCurrentFanfareSong);
+            interrupt_flag2 = DisableInterrupts();
+            m4aSongNumStart(songIndex);
+            musicPlayer->unk0 = 1;
+            musicPlayer->songIndex = songIndex;
+
+            if (volume == MAX_VOLUME)
+                musicPlayer->isNotMaxVolume = FALSE;
+            else
+                musicPlayer->isNotMaxVolume = TRUE;
+
+            musicPlayer->volume = volume;
+            if (interrupt_flag2)
+                EnableInterrupts();
         }
-      }
-      else
-      {
-        if (1 < (u16)(gFanfareMusicPlayerState - 1)) 
-        {
-            m4aMPlayStop(&gMPlayInfo_BGM);
-            m4aSongNumStart(gCurrentFanfareSong);
-            gFanfareMusicPlayerState = FANFARE_PLAYER_STATE_PLAYING;
-        }
-      }
-      switch(gCurrentBGSong)
-      {
-        case MUS_RAYQUAZAS_DOMAIN:
-        case MUS_FRIEND_AREA_STRATOS_LOOKOUT:
-        case MUS_FRIEND_AREA_RAINBOW_PEAK:
-        case MUS_DREAM_EATER:
-        case MUS_FRIEND_AREA_DEEPSEA_CURRENT:
-        case MUS_FRIEND_AREA_SEAFLOOR_CAVE:
-        case MUS_FRIEND_AREA_VOLCANIC_PIT:
-        case MUS_FRIEND_AREA_CRYPTIC_CAVE:
-        case MUS_THE_OTHER_SIDE:
-        case MUS_THE_MOUNTAIN_OF_FIRE:
-        case MUS_FRIEND_AREA_LEGENDARY_ISLAND:
-        case MUS_FRIEND_AREA_SOUTHERN_ISLAND:
-        case MUS_FRIEND_AREA_ENCLOSED_ISLAND:
-        case MUS_FRIEND_AREA_FINAL_ISLAND:
-        case MUS_FRIEND_AREA_HEALING_FOREST:
-            gRestartBGM = TRUE;
-            break;
-        default:
-            break;
-      }
-      if (interrupt_flag)
-        EnableInterrupts();
     }
-    else
-    {
-        nullsub_20(songIndex);
-    }
-  }
-  else
-  {
-    if (!IsSoundEffect(songIndex))
-      return;
-    playerIndex = GetMusicPlayerIndex(songIndex);
-    musicPlayer = &gBGMusicPlayers[playerIndex]; // need to load this before comparison to match
-    if (playerIndex < INDEX_SE1)
-        nullsub_20(songIndex);
-    else
-    {
-      interrupt_flag2 = DisableInterrupts();
-      m4aSongNumStart(songIndex);
-      musicPlayer->unk0 = 1;
-      musicPlayer->songIndex = songIndex;
-      if(volume == MAX_VOLUME)
-      {
-        musicPlayer->isNotMaxVolume = FALSE;
-      }
-      else
-      {
-        musicPlayer->isNotMaxVolume = TRUE;
-      }
-      musicPlayer->volume = volume;
-      if (interrupt_flag2)
-        EnableInterrupts();
-    }
-  }
 }
 
-void SetSoundEffectVolume(u16 songIndex, u16 volume)
+UNUSED static void SetSoundEffectVolume(u16 songIndex, u16 volume)
 {
-  bool8 interrupt_flag;
-  u16 playerIndex;
-  struct MusicPlayerInfo *info;
-  struct PMDMusicPlayer *musicPlayer;
+    bool8 interrupt_flag;
+    u16 playerIndex;
+    struct MusicPlayerInfo *info;
+    PMDMusicPlayer *musicPlayer;
 
-  if (MAX_VOLUME < volume) {
-    volume = MAX_VOLUME;
-  }
+    if (MAX_VOLUME < volume)
+        volume = MAX_VOLUME;
 
-  if ((!IsFanfare(songIndex)) && (IsSoundEffect(songIndex))) {
-    playerIndex = GetMusicPlayerIndex(songIndex);
-    info = gMPlayTable[playerIndex].info;
-    musicPlayer = &gBGMusicPlayers[playerIndex];
-    if (playerIndex >= INDEX_SE1) {
-      interrupt_flag = DisableInterrupts();
-      if (musicPlayer->songIndex == songIndex) {
-        m4aMPlayVolumeControl(info, 0xf, volume);
-      }
-      if (interrupt_flag)
-        EnableInterrupts();
+    if (!IsFanfare(songIndex) && IsSoundEffect(songIndex)) {
+        playerIndex = GetMusicPlayerIndex(songIndex);
+        info = gMPlayTable[playerIndex].info;
+        musicPlayer = &sBGMusicPlayers[playerIndex];
+        if (playerIndex >= INDEX_SE1) {
+            interrupt_flag = DisableInterrupts();
+            if (musicPlayer->songIndex == songIndex)
+                m4aMPlayVolumeControl(info, 0xf, volume);
+
+            if (interrupt_flag)
+                EnableInterrupts();
+        }
     }
-  }
 }
 
 void StopFanfareSE(u16 songIndex)
 {
     // Each section needs a var for interrupts..
-    char cVar1;
-    char cVar2;
-    char cVar3;
-    char cVar4;
+    bool8 cVar1;
+    bool8 cVar2;
+    bool8 cVar3;
+    bool8 cVar4;
 
     u32 playerIndex;
     s32 playerIndex2;
     struct MusicPlayerInfo *info;
-    struct PMDMusicPlayer *musicPlayer;
-    struct PMDMusicPlayer *musicPlayer1;
+    PMDMusicPlayer *musicPlayer;
+    PMDMusicPlayer *musicPlayer1;
 
     if (songIndex == STOP_SOUND_EFFECT) {
         cVar1 = DisableInterrupts();
 
-        for(playerIndex2 = INDEX_SE1, musicPlayer1 = &gSEMusicPlayers[0]; playerIndex2 < INDEX_SE6; playerIndex2++, musicPlayer1++)
-        {
+        for (playerIndex2 = INDEX_SE1, musicPlayer1 = &sSEMusicPlayers[0]; playerIndex2 < INDEX_SE6; playerIndex2++, musicPlayer1++) {
             m4aMPlayStop(gMPlayTable[playerIndex2].info);
             musicPlayer1->unk0 = 0;
             musicPlayer1->songIndex = STOP_SOUND_EFFECT;
             musicPlayer1->volume = 0;
             musicPlayer1->isNotMaxVolume = FALSE;
         }
-        if (cVar1 != '\0') {
+
+        if (cVar1)
             EnableInterrupts();
-        }
     }
-    else if (IsSoundEffect(songIndex))
-    {
+    else if (IsSoundEffect(songIndex)) {
         playerIndex = GetMusicPlayerIndex(songIndex);
         info = gMPlayTable[playerIndex].info;
-        musicPlayer = &gBGMusicPlayers[playerIndex];
-        if (playerIndex < INDEX_SE1) {
+        musicPlayer = &sBGMusicPlayers[playerIndex];
+
+        if (playerIndex < INDEX_SE1)
             nullsub_21(songIndex);
-        }
         else {
             cVar2 = DisableInterrupts();
+
             if (musicPlayer->songIndex == songIndex) {
                 m4aMPlayStop(info);
                 musicPlayer->unk0 = 0;
@@ -387,73 +369,69 @@ void StopFanfareSE(u16 songIndex)
                 musicPlayer->volume = 0;
                 musicPlayer->isNotMaxVolume = FALSE;
             }
-            if (cVar2 != '\0') {
+
+            if (cVar2)
                 EnableInterrupts();
-            }
         }
     }
-    else if (songIndex == STOP_FANFARE)
-    {
+    else if (songIndex == STOP_FANFARE) {
         cVar3 = DisableInterrupts();
-        if (gFanfareMusicPlayerState != 0) {
-            if (gCurrentFanfareSong != STOP_SOUND_EFFECT) {
-                gCurrentFanfareSong = STOP_SOUND_EFFECT;
+
+        if (sFanfareMusicPlayerState != 0) {
+            if (sCurrentFanfareSong != STOP_SOUND_EFFECT) {
+                sCurrentFanfareSong = STOP_SOUND_EFFECT;
                 m4aMPlayStop(&gMPlayInfo_Fanfare);
             }
         }
-        if (cVar3 != '\0') {
+
+        if (cVar3)
             EnableInterrupts();
-        }
     }
-    else if (IsFanfare(songIndex))
-    {
+    else if (IsFanfare(songIndex)) {
         cVar4 = DisableInterrupts();
-        if (gFanfareMusicPlayerState != 0) {
-            if (gCurrentFanfareSong == songIndex) {
-                gCurrentFanfareSong = STOP_SOUND_EFFECT;
+
+        if (sFanfareMusicPlayerState != 0) {
+            if (sCurrentFanfareSong == songIndex) {
+                sCurrentFanfareSong = STOP_SOUND_EFFECT;
                 m4aMPlayStop(&gMPlayInfo_Fanfare);
             }
         }
-        if (cVar4 != '\0') {
+
+        if (cVar4)
             EnableInterrupts();
-        }
     }
 }
 
 void FadeOutFanfareSE(u16 songIndex, u16 speed)
 {
-    char cVar1;
-    char cVar2;
-    char cVar3;
-    char cVar4;
+    bool8 cVar1;
+    bool8 cVar2;
+    bool8 cVar3;
+    bool8 cVar4;
     u32 comparison;
     s32 playerIndex2;
     u32 playerIndex;
-    struct PMDMusicPlayer *musicPlayer;
-    struct PMDMusicPlayer *musicPlayer1;
+    PMDMusicPlayer *musicPlayer;
+    PMDMusicPlayer *musicPlayer1;
     struct MusicPlayerInfo *playerInfo;
 
+// TODO: int16 memes
     comparison = 0x80 << 17; // 16777216
-    if((speed * 65536) > comparison)
-    {
+    if (speed * 65536 > comparison)
         speed = 16;
-    }
-    else
-    {
-        if((speed >>= 4) == 0)
-        {
+    else {
+        speed >>= 4;
+        if (speed == 0)
             speed = 1;
-        }
     }
 
     if (songIndex == STOP_SOUND_EFFECT) {
         cVar1 = DisableInterrupts();
-        for(playerIndex2 = INDEX_SE1, musicPlayer1 = &gSEMusicPlayers[0]; playerIndex2 < INDEX_SE6; playerIndex2++, musicPlayer1++)
-        {
+
+        for(playerIndex2 = INDEX_SE1, musicPlayer1 = &sSEMusicPlayers[0]; playerIndex2 < INDEX_SE6; playerIndex2++, musicPlayer1++) {
             if (musicPlayer1->songIndex != STOP_SOUND_EFFECT) {
-                if (IsMusicPlayerPlaying(playerIndex2)) {
-                    m4aMPlayFadeOut(gMPlayTable[playerIndex2].info,speed);
-                }
+                if (IsMusicPlayerPlaying(playerIndex2))
+                    m4aMPlayFadeOut(gMPlayTable[playerIndex2].info, speed);
                 else {
                     m4aMPlayStop(gMPlayTable[playerIndex2].info);
                     musicPlayer1->unk0 = 0;
@@ -463,19 +441,19 @@ void FadeOutFanfareSE(u16 songIndex, u16 speed)
                 }
             }
         }
-        if (cVar1 != '\0') {
+
+        if (cVar1)
             EnableInterrupts();
-        }
     }
     else if (IsSoundEffect(songIndex)) {
         playerIndex = GetMusicPlayerIndex(songIndex);
-        musicPlayer = &gBGMusicPlayers[playerIndex];
+        musicPlayer = &sBGMusicPlayers[playerIndex];
         playerInfo = gMPlayTable[playerIndex].info;
         cVar2 = DisableInterrupts();
+
         if (musicPlayer->songIndex != STOP_SOUND_EFFECT) {
-            if (IsMusicPlayerPlaying(playerIndex)) {
-                m4aMPlayFadeOut(playerInfo,speed);
-            }
+            if (IsMusicPlayerPlaying(playerIndex))
+                m4aMPlayFadeOut(playerInfo, speed);
             else {
                 m4aMPlayStop(playerInfo);
                 musicPlayer->unk0 = 0;
@@ -484,253 +462,228 @@ void FadeOutFanfareSE(u16 songIndex, u16 speed)
                 musicPlayer->isNotMaxVolume = FALSE;
             }
         }
-        if (cVar2 != '\0') {
+
+        if (cVar2)
             EnableInterrupts();
-        }
     }
     else if (songIndex == STOP_FANFARE) {
         cVar3 = DisableInterrupts();
-        if ((gFanfareMusicPlayerState != 0) && (gCurrentFanfareSong != STOP_SOUND_EFFECT)) {
-            if (IsMusicPlayerPlaying(INDEX_FANFARE)) {
-                m4aMPlayFadeOut(&gMPlayInfo_Fanfare,speed);
-            }
+
+        if (sFanfareMusicPlayerState != 0 && sCurrentFanfareSong != STOP_SOUND_EFFECT) {
+            if (IsMusicPlayerPlaying(INDEX_FANFARE))
+                m4aMPlayFadeOut(&gMPlayInfo_Fanfare, speed);
             else {
                 m4aMPlayStop(&gMPlayInfo_Fanfare);
-                gCurrentFanfareSong = STOP_SOUND_EFFECT;
+                sCurrentFanfareSong = STOP_SOUND_EFFECT;
             }
         }
-        if (cVar3 != '\0') {
+
+        if (cVar3)
             EnableInterrupts();
-        }
     }
     else if (IsFanfare(songIndex)) {
         cVar4 = DisableInterrupts();
-        if ((gFanfareMusicPlayerState != 0) && (gCurrentFanfareSong == songIndex)) {
-            if (IsMusicPlayerPlaying(INDEX_FANFARE)) {
-                m4aMPlayFadeOut(&gMPlayInfo_Fanfare,speed);
-            }
+
+        if (sFanfareMusicPlayerState != 0 && sCurrentFanfareSong == songIndex) {
+            if (IsMusicPlayerPlaying(INDEX_FANFARE))
+                m4aMPlayFadeOut(&gMPlayInfo_Fanfare, speed);
             else {
                 m4aMPlayStop(&gMPlayInfo_Fanfare);
-                gCurrentFanfareSong = STOP_SOUND_EFFECT;
+                sCurrentFanfareSong = STOP_SOUND_EFFECT;
             }
         }
-        if (cVar4 != '\0') {
+
+        if (cVar4)
             EnableInterrupts();
-        }
     }
 }
 
 bool8 IsFanfareSEPlaying(u16 songIndex)
 {
-  u32 playerIndex;
-  struct PMDMusicPlayer *musicPlayer;
-#ifndef NONMATCHING
-  register u32 songIndex_u32 asm("r4");
-  register u32 songIndex_u32_2 asm("r5");
-#else
-  u32 songIndex_u32;
-  u32 songIndex_u32_2;
-#endif
+    u32 playerIndex;
+    PMDMusicPlayer *musicPlayer;
+    #ifndef NONMATCHING
+    register u32 songIndex_u32 asm("r4");
+    register u32 songIndex_u32_2 asm("r5");
+    #else
+    u32 songIndex_u32;
+    u32 songIndex_u32_2;
+    #endif
 
-  songIndex_u32 = songIndex;
-  songIndex_u32_2 = songIndex_u32;
+    songIndex_u32 = songIndex;
+    songIndex_u32_2 = songIndex_u32;
 
-  if (IsFanfare(songIndex_u32)) {
-    if ((gFanfareMusicPlayerState != 0) && (gCurrentFanfareSong == songIndex_u32)) {
-      return TRUE;
+    if (IsFanfare(songIndex_u32)) {
+        if (sFanfareMusicPlayerState != 0 && sCurrentFanfareSong == songIndex_u32)
+            return TRUE;
     }
-  }
-  else
-  {
-    if (IsSoundEffect(songIndex_u32)) {
-      playerIndex = GetMusicPlayerIndex(songIndex_u32);
-      musicPlayer = &gBGMusicPlayers[playerIndex];
-      if ((INDEX_SE1 <= playerIndex) && (musicPlayer->songIndex == songIndex_u32_2)) {
-        return TRUE;
-      }
+    else {
+        if (IsSoundEffect(songIndex_u32)) {
+            playerIndex = GetMusicPlayerIndex(songIndex_u32);
+            musicPlayer = &sBGMusicPlayers[playerIndex];
+            if (INDEX_SE1 <= playerIndex && musicPlayer->songIndex == songIndex_u32_2)
+                return TRUE;
+        }
     }
-  }
-  return FALSE;
+
+    return FALSE;
 }
 
 void SoundVSync(void)
 {
-  u8 cVar1;
+    bool8 cVar1;
 
-  cVar1 = DisableInterrupts();
-  m4aSoundVSync();
-  if(cVar1)
-    EnableInterrupts();
+    cVar1 = DisableInterrupts();
+
+    m4aSoundVSync();
+
+    if (cVar1)
+        EnableInterrupts();
 }
 
-
 void nullsub_18(void)
 {
 }
 
 void UpdateSound(void)
 {
-    struct PMDMusicPlayer *musicPlayer; // r4
+    PMDMusicPlayer *musicPlayer; // r4
     s32 musicPlayerIndex; // r5
-    
+
     m4aSoundMain();
 
-    if(gFanfareMusicPlayerState != 0)
-    {
-        switch(gFanfareMusicPlayerState)
-        {
+    if (sFanfareMusicPlayerState != 0) {
+        switch (sFanfareMusicPlayerState) {
             case 1:
-                if (gMusicTransitionCounter != 0) 
-                {
-                    gMusicTransitionCounter--;
+                if (sMusicTransitionCounter != 0)
+                    sMusicTransitionCounter--;
+                else if (sCurrentFanfareSong == STOP_SOUND_EFFECT) {
+                    sFanfareMusicPlayerState = 4;
+                    sMusicTransitionCounter = 32;
                 }
-                else if (gCurrentFanfareSong == STOP_SOUND_EFFECT) 
-                {
-                    gFanfareMusicPlayerState = 4;
-                    gMusicTransitionCounter = 32;
-                }
-                else
-                {
-                    m4aSongNumStart(gCurrentFanfareSong);
-                    gFanfareMusicPlayerState = FANFARE_PLAYER_STATE_PLAYING;
+                else {
+                    m4aSongNumStart(sCurrentFanfareSong);
+                    sFanfareMusicPlayerState = FANFARE_PLAYER_STATE_PLAYING;
                 }
                 break;
             case 2:
-                if ((gCurrentBGSong != STOP_BGM) && (IsMusicPlayerPlaying(INDEX_BGM)))
+                if (sCurrentBGSong != STOP_BGM && IsMusicPlayerPlaying(INDEX_BGM))
                     break;
-                if (gCurrentFanfareSong == STOP_SOUND_EFFECT)
-                {
-                    gFanfareMusicPlayerState = 4;
-                    gMusicTransitionCounter = 32;
+
+                if (sCurrentFanfareSong == STOP_SOUND_EFFECT) {
+                    sFanfareMusicPlayerState = 4;
+                    sMusicTransitionCounter = 32;
                 }
-                else
-                {
-                    m4aSongNumStart(gCurrentFanfareSong);
-                    gFanfareMusicPlayerState = FANFARE_PLAYER_STATE_PLAYING;
+                else {
+                    m4aSongNumStart(sCurrentFanfareSong);
+                    sFanfareMusicPlayerState = FANFARE_PLAYER_STATE_PLAYING;
                 }
                 break;
             case 3:
-                if ((gCurrentFanfareSong != STOP_SOUND_EFFECT) && (!IsMusicPlayerPlaying(INDEX_FANFARE))) // INDEX_FANFARE
+                if (sCurrentFanfareSong != STOP_SOUND_EFFECT && !IsMusicPlayerPlaying(INDEX_FANFARE)) // INDEX_FANFARE
                     break;
-                else {
-                    gFanfareMusicPlayerState = 4;
-                    gMusicTransitionCounter = 32;
-                }
+
+                sFanfareMusicPlayerState = 4;
+                sMusicTransitionCounter = 32;
                 break;
             case 4:
-                if (gCurrentFanfareSong != STOP_SOUND_EFFECT) 
-                {
-                    if (IsMusicPlayerPlaying(INDEX_FANFARE)) break; // INDEX_FANFARE
+                if (sCurrentFanfareSong != STOP_SOUND_EFFECT) {
+                    if (IsMusicPlayerPlaying(INDEX_FANFARE))
+                        break; // INDEX_FANFARE
                 }
                 else
                     m4aMPlayStop(&gMPlayInfo_Fanfare);
 
-                if (gMusicTransitionCounter != 0) 
-                {
-                    gMusicTransitionCounter--;
+                if (sMusicTransitionCounter != 0) {
+                    sMusicTransitionCounter--;
                     break;
                 }
-                else if (gCurrentBGSong != STOP_BGM) 
-                {
-                    gBGMusicPlayerState = BG_PLAYER_STATE_PLAYING;
-                    if (gRestartBGM)
-                        m4aSongNumStart(gCurrentBGSong);
+
+                if (sCurrentBGSong != STOP_BGM) {
+                    sBGMusicPlayerstate = BG_PLAYER_STATE_PLAYING;
+
+                    if (sRestartBGM)
+                        m4aSongNumStart(sCurrentBGSong);
                     else
                         m4aMPlayFadeIn(&gMPlayInfo_BGM,4);
                 }
-                else 
-                {
-                    gBGMusicPlayerState = 0;
+                else {
+                    sBGMusicPlayerstate = 0;
                     m4aMPlayStop(&gMPlayInfo_BGM);
                 }
-                gFanfareMusicPlayerState = 0;
-                gCurrentFanfareSong = STOP_SOUND_EFFECT;
+
+                sFanfareMusicPlayerState = 0;
+                sCurrentFanfareSong = STOP_SOUND_EFFECT;
                 break;
         }
     }
-    else if (gBGMusicPlayerState != BG_PLAYER_STATE_INITIALIZE)
-    {
-        switch(gBGMusicPlayerState)
-        {
-
+    else if (sBGMusicPlayerstate != BG_PLAYER_STATE_INITIALIZE) {
+        switch (sBGMusicPlayerstate) {
             case BG_PLAYER_STATE_PLAYING:
-                if ((gCurrentBGSong == STOP_BGM) || IsMusicPlayerPlaying(INDEX_BGM)) // INDEX_BGM
-                {
-                    gBGMusicPlayerState = 2;
-                }
+                if (sCurrentBGSong == STOP_BGM || IsMusicPlayerPlaying(INDEX_BGM)) // INDEX_BGM
+                    sBGMusicPlayerstate = 2;
                 break;
             case 2:
             case 3:
-                if (gCurrentBGSong != STOP_BGM) 
-                {
-                    if (IsMusicPlayerPlaying(INDEX_BGM)) break; // INDEX_BGM
+                if (sCurrentBGSong != STOP_BGM) {
+                    if (IsMusicPlayerPlaying(INDEX_BGM))
+                        break; // INDEX_BGM
                 }
                 else
                     m4aMPlayStop(&gMPlayInfo_BGM);
-                gBGMusicPlayerState = 0;
-                gCurrentBGSong = STOP_BGM;
+
+                sBGMusicPlayerstate = 0;
+                sCurrentBGSong = STOP_BGM;
                 break;
-            case BG_PLAYER_STATE_STOPPED: // can also be other constants
+            case BG_PLAYER_STATE_STOPPED: // Can also be other constants
                 break;
         }
     }
-    else
-    {
-        if (!IsMusicPlayerPlaying(INDEX_BGM)) 
-        {
+    else {
+        if (!IsMusicPlayerPlaying(INDEX_BGM)) {
 #ifndef NONMATCHING
-            register u16 r2 asm("r2") = gQueuedBGSong, r1 = r2;
+            register u16 r2 asm("r2") = sQueuedBGSong, r1 = r2;
 #else
             u16 r2, r1;
-            r2 = gQueuedBGSong, r1 = r2;
+            r2 = sQueuedBGSong, r1 = r2;
 #endif
-            if (r1 != STOP_BGM) 
-            {
-                gBGMusicPlayerState = BG_PLAYER_STATE_PLAYING;
-                gCurrentBGSong = r2;
+            if (r1 != STOP_BGM) {
+                sBGMusicPlayerstate = BG_PLAYER_STATE_PLAYING;
+                sCurrentBGSong = r2;
                 m4aSongNumStart(r1);
-                gQueuedBGSong = STOP_BGM;
+                sQueuedBGSong = STOP_BGM;
             }
-            else 
-            {
-                gBGMusicPlayerState = 0;
-                gCurrentBGSong = STOP_BGM;
+            else {
+                sBGMusicPlayerstate = 0;
+                sCurrentBGSong = STOP_BGM;
             }
         }
     }
 
-    for(musicPlayerIndex = INDEX_SE1,  musicPlayer = &gSEMusicPlayers[0]; musicPlayerIndex < INDEX_SE6; musicPlayerIndex++, musicPlayer++)
-    {
-        if (musicPlayer->songIndex != STOP_SOUND_EFFECT) 
-        {
-            switch(musicPlayer->unk0)
-            {
-                    case 1:
-                        if ((musicPlayer->songIndex == STOP_BGM) || (IsMusicPlayerPlaying(musicPlayerIndex))) 
-                        {
-                            musicPlayer->unk0 = 2;
-                        }
-                        break;
-                    case 2:
-                        if (IsMusicPlayerPlaying(musicPlayerIndex))
-                        {
-                            if(musicPlayer->isNotMaxVolume)
-                            {
-                                musicPlayer->isNotMaxVolume = FALSE;
-                                m4aMPlayVolumeControl(gMPlayTable[musicPlayerIndex].info,0xff,musicPlayer->volume);
-                            }
-                        }
-                        else 
-                        {
-                            musicPlayer->unk0 = 0;
-                            musicPlayer->songIndex = STOP_SOUND_EFFECT;
-                            musicPlayer->volume = 0;
+    for (musicPlayerIndex = INDEX_SE1,  musicPlayer = &sSEMusicPlayers[0]; musicPlayerIndex < INDEX_SE6; musicPlayerIndex++, musicPlayer++) {
+        if (musicPlayer->songIndex != STOP_SOUND_EFFECT) {
+            switch (musicPlayer->unk0){
+                case 1:
+                    if (musicPlayer->songIndex == STOP_BGM || IsMusicPlayerPlaying(musicPlayerIndex))
+                        musicPlayer->unk0 = 2;
+                    break;
+                case 2:
+                    if (IsMusicPlayerPlaying(musicPlayerIndex)) {
+                        if (musicPlayer->isNotMaxVolume) {
                             musicPlayer->isNotMaxVolume = FALSE;
+                            m4aMPlayVolumeControl(gMPlayTable[musicPlayerIndex].info, 0xFF, musicPlayer->volume);
                         }
-                        break;
-                    case 3:
-                    case 0:
-                        break;
+                    }
+                    else {
+                        musicPlayer->unk0 = 0;
+                        musicPlayer->songIndex = STOP_SOUND_EFFECT;
+                        musicPlayer->volume = 0;
+                        musicPlayer->isNotMaxVolume = FALSE;
+                    }
+                    break;
+                case 3:
+                case 0:
+                    break;
             }
         }
     }
@@ -745,144 +698,116 @@ void StopBGMusicVSync(void)
     FadeOutFanfareSE(STOP_FANFARE, 0x10);
 
     interrupt_flag = DisableInterrupts();
-    if(gFanfareMusicPlayerState == 0)
-    {
-        if(gCurrentBGSong != STOP_BGM)
-        {
-            temp = gBGMusicPlayerState - 1;
-            if(temp <= 1)
-            {
-                if(gBGMusicPlayerState == 2)
-                {
-                    gRestartBGM = FALSE;
-                }
-                else if(gBGMusicPlayerState == BG_PLAYER_STATE_PLAYING)
-                {
-                    gRestartBGM = TRUE;
-                }
-                gBGMusicPlayerState = BG_PLAYER_STATE_STOPPED;
+
+    if (sFanfareMusicPlayerState == 0) {
+        if (sCurrentBGSong != STOP_BGM) {
+            temp = sBGMusicPlayerstate - 1;
+            if (temp <= 1) {
+                if (sBGMusicPlayerstate == 2)
+                    sRestartBGM = FALSE;
+                else if (sBGMusicPlayerstate == BG_PLAYER_STATE_PLAYING)
+                    sRestartBGM = TRUE;
+
+                sBGMusicPlayerstate = BG_PLAYER_STATE_STOPPED;
             }
         }
     }
+
     m4aMPlayStop(&gMPlayInfo_BGM);
     m4aSoundVSyncOff();
-    if(interrupt_flag)
-    {
+
+    if (interrupt_flag)
         EnableInterrupts();
-    }
 }
 
 void StartBGMusicVSync(void)
 {
     bool8 interrupt_flag = DisableInterrupts();
+
     m4aSoundVSyncOn();
-    if(gFanfareMusicPlayerState == 0)
-    {
-        if(gCurrentBGSong != STOP_BGM)
-        {
-            if(gBGMusicPlayerState == BG_PLAYER_STATE_STOPPED)
-            {
-                gBGMusicPlayerState = BG_PLAYER_STATE_PLAYING;
-                if(gRestartBGM)
-                {
-                    m4aSongNumStart(gCurrentBGSong);
-                }
+
+    if (sFanfareMusicPlayerState == 0) {
+        if (sCurrentBGSong != STOP_BGM) {
+            if (sBGMusicPlayerstate == BG_PLAYER_STATE_STOPPED) {
+                sBGMusicPlayerstate = BG_PLAYER_STATE_PLAYING;
+
+                if (sRestartBGM)
+                    m4aSongNumStart(sCurrentBGSong);
                 else
-                {
                     m4aMPlayContinue(&gMPlayInfo_BGM);
-                }
             }
         }
     }
-    if(interrupt_flag)
-    {
+
+    if (interrupt_flag)
         EnableInterrupts();
-    }
-
 }
 
-void nullsub_179(void)
+UNUSED static void nullsub_179(void)
 {
 }
 
-// Unused
-bool8 IsValidSong(u32 songIndex)
+UNUSED static bool8 IsValidSong(u32 songIndex)
 {
-    if(IsBGSong(songIndex))
-    {
-        if(GetMusicPlayerIndex(songIndex) == INDEX_BGM)
-        {
+    if (IsBGSong(songIndex)) {
+        if (GetMusicPlayerIndex(songIndex) == INDEX_BGM)
             return TRUE;
-        }
     }
-    if(IsFanfare(songIndex))
-    {
-        if(GetMusicPlayerIndex(songIndex) == INDEX_FANFARE)
-        {
+
+    if (IsFanfare(songIndex)) {
+        if (GetMusicPlayerIndex(songIndex) == INDEX_FANFARE)
             return TRUE;
-        }
     }
-    else if(IsSoundEffect(songIndex))
-    {
-        if(GetMusicPlayerIndex(songIndex) >= INDEX_SE1)
-        {
+    else if (IsSoundEffect(songIndex)) {
+        if (GetMusicPlayerIndex(songIndex) >= INDEX_SE1)
             return TRUE;
-        }
     }
+
     return FALSE;
 }
 
-void nullsub_19(void)
+static void nullsub_19(void)
 {
 }
 
-bool8 IsBGSong(u32 songIndex)
+static bool8 IsBGSong(u32 songIndex)
 {
-    if(songIndex <= NUM_BG_SONGS)
-    {
+    if (songIndex <= NUM_BG_SONGS)
         return TRUE;
-    }
     return FALSE;
 }
 
-bool8 IsSoundEffect(u32 songIndex)
+static bool8 IsSoundEffect(u32 songIndex)
 {
-    if(songIndex - SOUND_EFFECTS_START_INDEX <= NUM_SOUND_EFFECTS)
-    {
+    if (songIndex - SOUND_EFFECTS_START_INDEX <= NUM_SOUND_EFFECTS)
         return TRUE;
-    }
     return FALSE;
 }
 
-bool8 IsFanfare(u32 songIndex)
+static bool8 IsFanfare(u32 songIndex)
 {
-    if(songIndex - FANFARE_START_INDEX <= NUM_FANFARES)
-    {
+    if (songIndex - FANFARE_START_INDEX <= NUM_FANFARES)
         return TRUE;
-    }
     return FALSE;
 }
 
-u16 GetMusicPlayerIndex(u16 songIndex)
+static u16 GetMusicPlayerIndex(u16 songIndex)
 {
     return gSongTable[songIndex].ms;
 }
 
-bool8 IsMusicPlayerPlaying(u16 playerIndex)
+static bool8 IsMusicPlayerPlaying(u16 playerIndex)
 {
     // Had to cast this.. m4a_internal header has this as u32
-    if((u16)gMPlayTable[playerIndex].info->status == 0)
-    {
+    if ((u16)gMPlayTable[playerIndex].info->status == 0)
         return FALSE;
-    }
     return TRUE;
 }
 
-void nullsub_20(u16 songIndex)
+static void nullsub_20(u16 songIndex)
 {
 }
 
-void nullsub_21(u16 songIndex)
+static void nullsub_21(u16 songIndex)
 {
-}
-
+}
\ No newline at end of file
diff --git a/src/save.c b/src/save.c
index 76a40262e..341b673b0 100644
--- a/src/save.c
+++ b/src/save.c
@@ -57,7 +57,7 @@ extern u32 sub_8097D60(u8 *, u32);
 extern u32 sub_8097D98(void* a, s32 b);
 extern void sub_800135C(void);
 extern void sub_80958E4(u32 *a, u32 b);
-extern struct unkStruct_203B490 *GetMailInfo(void);
+extern unkStruct_203B490 *GetMailInfo(void);
 extern void InitializeMailJobsNews(void);
 extern void sub_80972F4(void);
 extern void sub_80974E8(void);
diff --git a/src/save_read.c b/src/save_read.c
index 7000111bb..a5f1a8111 100644
--- a/src/save_read.c
+++ b/src/save_read.c
@@ -4,13 +4,13 @@
 #include "save.h"
 #include "save_read.h"
 
-EWRAM_DATA_2 struct SavePakRead *gSavePakRead = {0};
+EWRAM_DATA_2 SavePakRead *gSavePakRead = {0};
 
 #include "data/save_read.h"
 
 void PrepareSavePakRead(void)
 {
-    gSavePakRead = MemoryAlloc(sizeof(struct SavePakRead), 5);
+    gSavePakRead = MemoryAlloc(sizeof(SavePakRead), 5);
     gSavePakRead->state = 1;
 }