diff --git a/asm/object/giantBookLadder.s b/asm/object/giantBookLadder.s
deleted file mode 100644
index a17733ef..00000000
--- a/asm/object/giantBookLadder.s
+++ /dev/null
@@ -1,241 +0,0 @@
-	.include "asm/macros.inc"
-
-	.include "constants/constants.inc"
-
-	.syntax unified
-
-	.text
-
-
-	thumb_func_start GiantBookLadder
-GiantBookLadder: @ 0x0808E4A8
-	push {r4, r5, r6, lr}
-	adds r4, r0, #0
-	ldrb r2, [r4, #0xa]
-	lsls r1, r2, #1
-	ldr r0, _0808E540 @ =gUnk_08121C40
-	adds r3, r1, r0
-	ldrb r6, [r4, #0xc]
-	cmp r6, #0
-	bne _0808E54C
-	movs r5, #1
-	strb r5, [r4, #0xc]
-	movs r2, #0
-	ldrb r0, [r4, #0xb]
-	cmp r0, #0
-	bne _0808E4C8
-	movs r2, #1
-_0808E4C8:
-	ldrb r1, [r4, #0x18]
-	movs r0, #4
-	rsbs r0, r0, #0
-	ands r0, r1
-	orrs r0, r2
-	strb r0, [r4, #0x18]
-	ldrb r0, [r4, #0xa]
-	strb r0, [r4, #0x1e]
-	adds r0, r4, #0
-	adds r0, #0x38
-	strb r5, [r0]
-	ldrb r1, [r3]
-	lsls r1, r1, #6
-	ldrb r2, [r4, #0x19]
-	movs r0, #0x3f
-	ands r0, r2
-	orrs r0, r1
-	strb r0, [r4, #0x19]
-	ldrb r0, [r3, #1]
-	adds r3, r4, #0
-	adds r3, #0x29
-	movs r1, #7
-	ands r1, r0
-	ldrb r2, [r3]
-	movs r0, #8
-	rsbs r0, r0, #0
-	ands r0, r2
-	orrs r0, r1
-	strb r0, [r3]
-	adds r0, r4, #0
-	adds r0, #0x76
-	strh r6, [r0]
-	movs r0, #0x2e
-	ldrsh r1, [r4, r0]
-	ldr r2, _0808E544 @ =gRoomControls
-	ldrh r0, [r2, #6]
-	subs r1, r1, r0
-	asrs r1, r1, #4
-	movs r3, #0x3f
-	ands r1, r3
-	movs r5, #0x32
-	ldrsh r0, [r4, r5]
-	ldrh r2, [r2, #8]
-	subs r0, r0, r2
-	asrs r0, r0, #4
-	ands r0, r3
-	lsls r0, r0, #6
-	orrs r1, r0
-	adds r0, r4, #0
-	adds r0, #0x74
-	strh r1, [r0]
-	adds r0, r4, #0
-	bl sub_0808E55C
-	ldr r1, _0808E548 @ =sub_0808E55C
-	adds r0, r4, #0
-	movs r2, #0
-	bl RegisterTransitionManager
-	b _0808E55A
-	.align 2, 0
-_0808E540: .4byte gUnk_08121C40
-_0808E544: .4byte gRoomControls
-_0808E548: .4byte sub_0808E55C
-_0808E54C:
-	movs r0, #1
-	ands r2, r0
-	cmp r2, #0
-	bne _0808E55A
-	adds r0, r4, #0
-	bl sub_0808E670
-_0808E55A:
-	pop {r4, r5, r6, pc}
-
-	thumb_func_start sub_0808E55C
-sub_0808E55C: @ 0x0808E55C
-	push {r4, r5, r6, r7, lr}
-	mov r7, sb
-	mov r6, r8
-	push {r6, r7}
-	mov r8, r0
-	ldrb r0, [r0, #0xa]
-	cmp r0, #1
-	beq _0808E614
-	cmp r0, #1
-	bgt _0808E576
-	cmp r0, #0
-	beq _0808E57A
-	b _0808E63A
-_0808E576:
-	cmp r0, #2
-	bne _0808E63A
-_0808E57A:
-	mov r0, r8
-	adds r0, #0x74
-	ldrh r6, [r0]
-	ldr r0, _0808E5FC @ =0xFFFFFEFF
-	adds r7, r6, r0
-	ldr r4, _0808E600 @ =0x0000408F
-	mov r5, r8
-	adds r5, #0x38
-	ldrb r2, [r5]
-	adds r0, r4, #0
-	adds r1, r7, #0
-	bl SetTile
-	ldr r2, _0808E604 @ =0xFFFFFF00
-	adds r1, r6, r2
-	ldrb r2, [r5]
-	adds r0, r4, #0
-	bl SetTile
-	ldr r0, _0808E608 @ =0x0000406C
-	ldr r2, _0808E60C @ =0xFFFFFEFE
-	adds r1, r6, r2
-	ldrb r2, [r5]
-	bl SetTile
-	ldr r0, _0808E610 @ =0x0000406D
-	adds r1, r6, #0
-	subs r1, #0xff
-	ldrb r2, [r5]
-	bl SetTile
-	mov r1, r8
-	ldrb r0, [r1, #0xa]
-	movs r2, #6
-	mov sb, r2
-	cmp r0, #0
-	beq _0808E63A
-	movs r0, #4
-	mov sb, r0
-	subs r4, #0x1d
-	adds r1, r6, #0
-	adds r1, #0x3f
-	ldrb r2, [r5]
-	adds r0, r4, #0
-	bl SetTile
-	adds r1, r6, #0
-	adds r1, #0x40
-	ldrb r2, [r5]
-	adds r0, r4, #0
-	bl SetTile
-	adds r1, r6, #0
-	adds r1, #0x7f
-	ldrb r2, [r5]
-	adds r0, r4, #0
-	bl SetTile
-	adds r1, r6, #0
-	adds r1, #0x80
-	ldrb r2, [r5]
-	adds r0, r4, #0
-	bl SetTile
-	b _0808E63A
-	.align 2, 0
-_0808E5FC: .4byte 0xFFFFFEFF
-_0808E600: .4byte 0x0000408F
-_0808E604: .4byte 0xFFFFFF00
-_0808E608: .4byte 0x0000406C
-_0808E60C: .4byte 0xFFFFFEFE
-_0808E610: .4byte 0x0000406D
-_0808E614:
-	mov r0, r8
-	adds r0, #0x74
-	ldrh r6, [r0]
-	subs r7, r6, #1
-	ldr r5, _0808E66C @ =0x0000408E
-	mov r4, r8
-	adds r4, #0x38
-	ldrb r2, [r4]
-	adds r0, r5, #0
-	adds r1, r7, #0
-	bl SetTile
-	ldrb r2, [r4]
-	adds r0, r5, #0
-	adds r1, r6, #0
-	bl SetTile
-	movs r1, #2
-	mov sb, r1
-_0808E63A:
-	movs r5, #0
-	cmp r5, sb
-	bhs _0808E662
-	ldr r6, _0808E66C @ =0x0000408E
-	mov r4, r8
-	adds r4, #0x38
-_0808E646:
-	adds r7, #0x40
-	ldrb r2, [r4]
-	adds r0, r6, #0
-	adds r1, r7, #0
-	bl SetTile
-	adds r1, r7, #1
-	ldrb r2, [r4]
-	adds r0, r6, #0
-	bl SetTile
-	adds r5, #1
-	cmp r5, sb
-	blo _0808E646
-_0808E662:
-	pop {r3, r4}
-	mov r8, r3
-	mov sb, r4
-	pop {r4, r5, r6, r7, pc}
-	.align 2, 0
-_0808E66C: .4byte 0x0000408E
-
-	thumb_func_start sub_0808E670
-sub_0808E670: @ 0x0808E670
-	push {lr}
-	adds r0, #0x74
-	ldrh r0, [r0]
-	ldr r1, _0808E684 @ =0xFFFFFEFF
-	adds r0, r0, r1
-	movs r1, #1
-	bl GetTileType
-	pop {pc}
-	.align 2, 0
-_0808E684: .4byte 0xFFFFFEFF
diff --git a/assets/assets.json b/assets/assets.json
index 67b70be6..410ef933 100644
--- a/assets/assets.json
+++ b/assets/assets.json
@@ -43691,11 +43691,6 @@
     "size": 60,
     "type": "animation"
   },
-  {
-    "path": "giantBookLadder/gUnk_08121C40.bin",
-    "start": 1186880,
-    "size": 8
-  },
   {
     "path": "heartContainer/gUnk_08121C58.bin",
     "start": 1186904,
diff --git a/data/const/object/giantBookLadder.s b/data/const/object/giantBookLadder.s
deleted file mode 100644
index 1833180a..00000000
--- a/data/const/object/giantBookLadder.s
+++ /dev/null
@@ -1,8 +0,0 @@
-	.include "asm/macros.inc"
-	.include "constants/constants.inc"
-
-	.section .rodata
-    .align 2
-
-gUnk_08121C40:: @ 08121C40
-	.incbin "giantBookLadder/gUnk_08121C40.bin"
diff --git a/linker.ld b/linker.ld
index 14101c7e..b8cd4128 100644
--- a/linker.ld
+++ b/linker.ld
@@ -715,7 +715,7 @@ SECTIONS {
         asm/object/object43.o(.text);
         asm/object/object44.o(.text);
         asm/object/object45.o(.text);
-        asm/object/giantBookLadder.o(.text);
+        src/object/giantBookLadder.o(.text);
         src/object/heartContainer.o(.text);
         src/object/fileScreenObjects.o(.text);
         src/object/object49.o(.text);
@@ -1452,7 +1452,7 @@ SECTIONS {
         data/animations/object/object44.o(.rodata);
         data/const/object/object45.o(.rodata);
         data/animations/object/object45.o(.rodata);
-        data/const/object/giantBookLadder.o(.rodata);
+        src/object/giantBookLadder.o(.rodata);
         src/object/heartContainer.o(.rodata);
         data/const/object/heartContainer.o(.rodata);
         data/const/object/fileScreenObjects.o(.rodata);
diff --git a/src/object/giantBookLadder.c b/src/object/giantBookLadder.c
new file mode 100644
index 00000000..5983787b
--- /dev/null
+++ b/src/object/giantBookLadder.c
@@ -0,0 +1,80 @@
+#define NENT_DEPRECATED
+#include "object.h"
+#include "manager.h"
+
+typedef struct {
+    Entity base;
+    u8 filler[0xc];
+    u16 unk74;
+    u16 unk76;
+} GiantBookLadderEntity;
+
+void sub_0808E55C(GiantBookLadderEntity*);
+u32 sub_0808E670(GiantBookLadderEntity*);
+
+void GiantBookLadder(Entity* this) {
+    static const u8 spriteDefs[] = {
+        3, 7, 3, 7, 3, 6, 0, 0,
+    };
+    const u8* spriteDefPtr = &spriteDefs[this->type * 2];
+    if (this->action == 0) {
+        this->action = 1;
+        this->spriteSettings.draw = this->type2 == 0;
+        this->frameIndex = this->type;
+        this->collisionLayer = 1;
+        this->spriteRendering.b3 = spriteDefPtr[0];
+        this->spritePriority.b0 = spriteDefPtr[1];
+        ((GiantBookLadderEntity*)this)->unk76 = 0;
+        ((GiantBookLadderEntity*)this)->unk74 = COORD_TO_TILE(this);
+        sub_0808E55C((GiantBookLadderEntity*)this);
+        RegisterTransitionManager(this, sub_0808E55C, 0);
+    } else if ((this->type & 1) == 0) {
+        sub_0808E670((GiantBookLadderEntity*)this);
+    }
+}
+
+void sub_0808E55C(GiantBookLadderEntity* this) {
+    u32 type;
+    u32 uVar4;
+    u32 unaff_r9;
+    u32 uVar5;
+    u32 position;
+
+    switch (super->type) {
+        case 0:
+        case 2:
+            position = this->unk74;
+            unaff_r9 = position - 0x101;
+            SetTile(0x408f, unaff_r9, super->collisionLayer);
+            SetTile(0x408f, position - 0x100, super->collisionLayer);
+            SetTile(0x406c, position - 0x102, super->collisionLayer);
+            SetTile(0x406d, position - 0xff, super->collisionLayer);
+            type = super->type;
+            uVar5 = 6;
+            if (type != 0) {
+                uVar5 = 4;
+                SetTile(0x4072, position + 0x3f, super->collisionLayer);
+                SetTile(0x4072, position + 0x40, super->collisionLayer);
+                SetTile(0x4072, position + 0x7f, super->collisionLayer);
+                SetTile(0x4072, position + 0x80, super->collisionLayer);
+            }
+            break;
+        case 1:
+            position = this->unk74;
+            unaff_r9 = position - 1;
+            SetTile(0x408e, unaff_r9, super->collisionLayer);
+            SetTile(0x408e, position, super->collisionLayer);
+            uVar5 = 2;
+            break;
+    }
+
+    for (uVar4 = 0; uVar4 < uVar5; uVar4++) {
+        unaff_r9 += 0x40;
+        SetTile(0x408e, unaff_r9, super->collisionLayer);
+        SetTile(0x408e, unaff_r9 + 1, super->collisionLayer);
+    }
+}
+
+u32 sub_0808E670(GiantBookLadderEntity* this) {
+    return GetTileType(this->unk74 - 0x101, 1);
+}