diff --git a/include/code_805D8C8.h b/include/code_805D8C8.h
index 5543c1ccb..075b7ea08 100644
--- a/include/code_805D8C8.h
+++ b/include/code_805D8C8.h
@@ -3,11 +3,11 @@
 
 #include "sprite.h"
 
-extern struct Dungeon_ax *sub_80687D0(s16);
-/*struct Dungeon_ax *sub_80687D0(s16 species)
+extern struct OpenedFile *sub_80687D0(s16);
+/*struct OpenedFile *sub_80687D0(s16 species)
 {
     s32 species32 = species;
-    return gDungeon->sub17B44[species32];
+    return gDungeon->sprites[species32];
 }*/
 
 #endif // GUARD_CODE_805D8C8_H
\ No newline at end of file
diff --git a/include/dungeon_entity.h b/include/dungeon_entity.h
index 479cba39b..450e53f96 100644
--- a/include/dungeon_entity.h
+++ b/include/dungeon_entity.h
@@ -272,7 +272,7 @@ struct Entity
     // gets assigned the current counter value as its spawn index.
     /* 0x26 */ u16 spawnGenID;
     /* 0x28*/ struct EntitySpriteInfo spriteInfo;
-    struct Dungeon_ax *unk64;
+    struct OpenedFile *unk64;
     s16 unk68;
     u8 unk6A;
     u8 unk6B;
diff --git a/include/dungeon_global_data.h b/include/dungeon_global_data.h
index b8d3a1a70..b4b3c0161 100644
--- a/include/dungeon_global_data.h
+++ b/include/dungeon_global_data.h
@@ -1,9 +1,10 @@
 #ifndef GUARD_DUNGEON_DATA_H
 #define GUARD_DUNGEON_DATA_H
 
+#include "global.h"
 #include "constants/monster.h"
 #include "dungeon_entity.h"
-#include "global.h"
+#include "file_system.h"
 #include "map.h"
 #include "position.h"
 #include "sprite.h"
@@ -199,8 +200,8 @@ struct Dungeon
     /* 0x17B38 */ u32 unk17B38;
     /* 0x17B3C */ u32 unk17B3C;
     u8 fill17B40[0x17B44 - 0x17B40];
-    struct Dungeon_ax *sub17B44[MONSTER_MAX]; // Assuming MONSTER_MAX since the highest value I've seen read is MONSTER_DECOY
-    u8 fill181E0[0x181E8 - 0x181E0];
+    /* 0x17B44 */ struct OpenedFile *sprites[MONSTER_MAX + 1];
+    u8 fill181E4[0x181E8 - 0x181E4];
     /* 0x181E8 */ struct Position cameraPos;
     /* 0x181EC */ struct Position cameraPosMirror;
     /* 0x181F0 */ struct Position cameraPixelPos;
diff --git a/include/file_system.h b/include/file_system.h
index 83b7c5d61..8ce24a15e 100644
--- a/include/file_system.h
+++ b/include/file_system.h
@@ -1,35 +1,40 @@
 #ifndef GUARD_FILE_SYSTEM_H
 #define GUARD_FILE_SYSTEM_H
 
+// size: 0x8
 struct File
 {
-    char *name;
-    u8 *data;
+    /* 0x0 */ char *name;
+    /* 0x4 */ u8 *data;
 };
 
+// size: 0x8
 struct OpenedFile
 {
-    struct File *file;
-    u8 *data;
+    /* 0x0 */ struct File *file;
+    /* 0x4 */ u8 *data;
 };
 
+// size: 0x10
 struct FileArchive
 {
-    char magic[8];
-    s32 count;
-    struct File *entries;
+    /* 0x0 */ char magic[8];
+    /* 0x8 */ s32 count;
+    /* 0xC */ struct File *entries;
 };
 
+// size: 0x8
 struct SiroArchive
 {
-    u32 magic;
-    u8 *data;
+    /* 0x0 */ u32 magic;
+    /* 0x4 */ u8 *data;
 };
 
+// size: 0x8
 struct UnkFileStruct1
 {
-    /* 0x0 */ u32 unk0;
-    /* 0x4 */ u32 unk4;
+    u32 unk0;
+    u32 unk4;
 };
 
 void InitFileSystem(void);
diff --git a/include/sprite.h b/include/sprite.h
index 349965629..1e217b36e 100644
--- a/include/sprite.h
+++ b/include/sprite.h
@@ -65,7 +65,7 @@ struct EntitySpriteInfo
 };
 
 // size: ?
-struct Dungeon_ax_Sub4
+struct Dungeon_ax
 {
     u32 unk0;
     u32 **unk4;
@@ -74,13 +74,6 @@ struct Dungeon_ax_Sub4
     u32 unk10;
 };
 
-// size: ?
-struct Dungeon_ax
-{
-    u8 fill0[0x4 - 0x0];
-    struct Dungeon_ax_Sub4 *unk4;
-};
-
 void AddSprite(struct SpriteOAM *, s32, struct UnkSpriteMem *, struct unkStruct_2039DB0 *);
 void BlinkSavingIcon(void);
 void CopySpritesToOam(void);
@@ -90,9 +83,9 @@ void SetSavingIconCoords(struct Position *);
 void sub_8004E8C(struct unkStruct_2039DB0 *);
 void sub_8005180(void);
 void sub_8005304(void);
-void sub_80053AC(struct EntitySpriteInfo *, struct Dungeon_ax *, u32, u32, u32, u32, bool8);
-void sub_80053D0(struct EntitySpriteInfo *, struct Dungeon_ax_Sub4 *, u32, u32, u32, u32, bool8);
-void sub_800543C(struct EntitySpriteInfo *, struct Dungeon_ax *, u32, u32, u32, bool8);
+void sub_80053AC(struct EntitySpriteInfo *, struct OpenedFile *, u32, u32, u32, u32, bool8);
+void sub_80053D0(struct EntitySpriteInfo *, struct Dungeon_ax *, u32, u32, u32, u32, bool8);
+void sub_800543C(struct EntitySpriteInfo *, struct OpenedFile *, u32, u32, u32, bool8);
 void sub_80054BC(struct axPokemon *);
 
 #endif // GUARD_SPRITE_H
\ No newline at end of file
diff --git a/src/code_8077274_1.c b/src/code_8077274_1.c
index 77bbbffa7..358133b1c 100644
--- a/src/code_8077274_1.c
+++ b/src/code_8077274_1.c
@@ -244,7 +244,7 @@ void sub_8078E18(struct Entity * pokemon, struct Entity * target)
     s16 apparentID_s16;
     s32 index;
     struct EntityInfo *entityInfo;
-    struct Dungeon_ax *iVar9;
+    struct OpenedFile *iVar9;
     struct PokemonStruct *auStack544[128];
 
     if (!EntityExists(target))
diff --git a/src/sprite.c b/src/sprite.c
index 676d7eb1b..e80999b93 100644
--- a/src/sprite.c
+++ b/src/sprite.c
@@ -20,7 +20,7 @@ extern struct unkStruct_20266B0 *gUnknown_203B074;
 extern void nullsub_3(s32, s32);
 
 void RegisterSpriteParts_80052BC(struct UnkSpriteMem *);
-void sub_800545C(struct EntitySpriteInfo *, struct Dungeon_ax_Sub4 *, u32, u32, u32, bool8);
+void sub_800545C(struct EntitySpriteInfo *, struct Dungeon_ax *, u32, u32, u32, bool8);
 
 void InitSprites(void)
 {
@@ -886,12 +886,12 @@ void sub_800533C(struct ax_pose **a0, struct UnkSpriteMem **a1, struct axdata1 *
     }
 }
 
-void sub_80053AC(struct EntitySpriteInfo *a0, struct Dungeon_ax *a1, u32 a2, u32 a3, u32 a4, u32 spriteAnimIndex, bool8 a6)
+void sub_80053AC(struct EntitySpriteInfo *a0, struct OpenedFile *a1, u32 a2, u32 a3, u32 a4, u32 spriteAnimIndex, bool8 a6)
 {
-    sub_80053D0(a0, a1->unk4, a2, a3, a4, spriteAnimIndex, a6);
+    sub_80053D0(a0, (struct Dungeon_ax *)a1->data, a2, a3, a4, spriteAnimIndex, a6);
 }
 
-void sub_80053D0(struct EntitySpriteInfo *a0, struct Dungeon_ax_Sub4 *a1, u32 a2, u32 direction, u32 a4, u32 spriteAnimIndex, bool8 a6)
+void sub_80053D0(struct EntitySpriteInfo *a0, struct Dungeon_ax *a1, u32 a2, u32 direction, u32 a4, u32 spriteAnimIndex, bool8 a6)
 {
     a0->unk0 = 0x8000;
     if (a6)
@@ -914,12 +914,12 @@ void sub_80053D0(struct EntitySpriteInfo *a0, struct Dungeon_ax_Sub4 *a1, u32 a2
     a0->unk30 = a1->unk10;
 }
 
-void sub_800543C(struct EntitySpriteInfo *a0, struct Dungeon_ax *a1, u32 a2, u32 a3, u32 spriteAnimIndex, bool8 a5)
+void sub_800543C(struct EntitySpriteInfo *a0, struct OpenedFile *a1, u32 a2, u32 a3, u32 spriteAnimIndex, bool8 a5)
 {
-    sub_800545C(a0, a1->unk4, a2, a3, spriteAnimIndex, a5);
+    sub_800545C(a0, (struct Dungeon_ax *)a1->data, a2, a3, spriteAnimIndex, a5);
 }
 
-void sub_800545C(struct EntitySpriteInfo *a0, struct Dungeon_ax_Sub4 *a1, u32 a2, u32 a3, u32 spriteAnimIndex, bool8 a5)
+void sub_800545C(struct EntitySpriteInfo *a0, struct Dungeon_ax *a1, u32 a2, u32 a3, u32 spriteAnimIndex, bool8 a5)
 {
     a0->unk0 = 0x8000;
     if (a5)