diff --git a/asm/code_800D090.s b/asm/code_800D090.s
index a6f1c4b42..132e51544 100644
--- a/asm/code_800D090.s
+++ b/asm/code_800D090.s
@@ -5,499 +5,8 @@
 
 	.text
 
-	thumb_func_start sub_800D224
-sub_800D224:
-	push {r4-r7,lr}
-	mov r7, r10
-	mov r6, r9
-	mov r5, r8
-	push {r5-r7}
-	sub sp, 0x4
-	str r0, [sp]
-	movs r6, 0
-	ldr r0, _0800D280
-	mov r12, r0
-	ldr r1, _0800D284
-	mov r10, r1
-	movs r2, 0x2
-	mov r9, r2
-_0800D240:
-	ldr r1, [sp]
-	asrs r1, r6
-	movs r0, 0x1
-	ands r1, r0
-	adds r3, r6, 0x1
-	mov r8, r3
-	cmp r1, 0
-	beq _0800D2CE
-	lsls r0, r6, 2
-	ldr r1, _0800D288
-	adds r2, r0, r1
-	ldr r1, [r2]
-	adds r5, r0, 0
-	cmp r1, 0x1
-	bne _0800D2CE
-	lsls r0, r6, 5
-	adds r0, r6
-	lsls r0, 3
-	ldr r1, _0800D28C
-	adds r7, r0, r1
-	movs r4, 0
-	mov r3, r12
-	adds r0, r5, r3
-	ldr r1, [r0]
-	mov r3, r10
-	ldr r0, [r3]
-	lsrs r0, 1
-	cmp r1, r0
-	bcc _0800D290
-	mov r0, r9
-	str r0, [r2]
-	b _0800D2C4
-	.align 2, 0
-_0800D280: .4byte gUnknown_202DB58
-_0800D284: .4byte gUnknown_202DB74
-_0800D288: .4byte gUnknown_202DB60
-_0800D28C: .4byte gUnknown_202D910
-_0800D290:
-	mov r1, r12
-	adds r0, r5, r1
-	ldr r3, [r0]
-	adds r2, r3, r4
-	lsls r2, 1
-	adds r2, r7
-	lsls r0, r4, 1
-	lsls r1, r6, 4
-	adds r0, r1
-	ldr r1, _0800D2E4
-	adds r0, r1
-	ldrh r0, [r0]
-	strh r0, [r2]
-	adds r4, 0x1
-	cmp r4, 0x7
-	bhi _0800D2C4
-	adds r1, r3, r4
-	mov r2, r10
-	ldr r0, [r2]
-	lsrs r0, 1
-	cmp r1, r0
-	bcc _0800D290
-	ldr r3, _0800D2E8
-	adds r0, r5, r3
-	mov r1, r9
-	str r1, [r0]
-_0800D2C4:
-	mov r2, r12
-	adds r1, r5, r2
-	ldr r0, [r1]
-	adds r0, 0x8
-	str r0, [r1]
-_0800D2CE:
-	mov r6, r8
-	cmp r6, 0x1
-	ble _0800D240
-	add sp, 0x4
-	pop {r3-r5}
-	mov r8, r3
-	mov r9, r4
-	mov r10, r5
-	pop {r4-r7}
-	pop {r0}
-	bx r0
-	.align 2, 0
-_0800D2E4: .4byte gUnknown_202DB30
-_0800D2E8: .4byte gUnknown_202DB60
-	thumb_func_end sub_800D224
 
-	thumb_func_start sub_800D2EC
-sub_800D2EC:
-	push {r4-r7,lr}
-	ldr r0, _0800D318
-	mov r12, r0
-	ldr r3, _0800D31C
-	adds r7, r3, 0
-	ldr r6, _0800D320
-	ldr r2, _0800D324
-	adds r5, r2, 0
-	adds r5, 0xE
-	ldr r4, _0800D328
-_0800D300:
-	ldr r0, [r4]
-	lsrs r0, 1
-	ldr r1, [r7]
-	cmp r1, r0
-	bcs _0800D32C
-	lsls r0, r1, 1
-	add r0, r12
-	ldrh r0, [r0]
-	strh r0, [r2]
-	adds r0, r1, 0x1
-	str r0, [r3]
-	b _0800D32E
-	.align 2, 0
-_0800D318: .4byte gUnknown_202D808
-_0800D31C: .4byte gUnknown_202DB50
-_0800D320: .4byte 0x0000fcfc
-_0800D324: .4byte gUnknown_202DB20
-_0800D328: .4byte gUnknown_202DB74
-_0800D32C:
-	strh r6, [r2]
-_0800D32E:
-	adds r2, 0x2
-	cmp r2, r5
-	bls _0800D300
-	pop {r4-r7}
-	pop {r0}
-	bx r0
-	thumb_func_end sub_800D2EC
 
-	thumb_func_start sub_800D33C
-sub_800D33C:
-	push {r4,r5,lr}
-	movs r5, 0
-	ldr r1, _0800D370
-	ldr r4, _0800D374
-	ldr r0, [r4]
-	str r0, [r1]
-	ldr r0, _0800D378
-	ldr r1, _0800D37C
-	bl sub_800D820
-	adds r2, r0, 0
-	str r2, [r4]
-	ldr r1, _0800D380
-	ldrb r0, [r1]
-	cmp r0, 0
-	bne _0800D384
-	movs r0, 0x80
-	lsls r0, 1
-	ands r0, r2
-	cmp r0, 0
-	beq _0800D36A
-	movs r0, 0x1
-	strb r0, [r1]
-_0800D36A:
-	movs r0, 0
-	b _0800D40E
-	.align 2, 0
-_0800D370: .4byte gUnknown_202DB6C
-_0800D374: .4byte gUnknown_202DB68
-_0800D378: .4byte gUnknown_202DB20
-_0800D37C: .4byte gUnknown_202DB30
-_0800D380: .4byte gUnknown_202DB70
-_0800D384:
-	movs r0, 0x80
-	lsls r0, 5
-	ands r0, r2
-	cmp r0, 0
-	beq _0800D392
-	movs r0, 0x3
-	b _0800D40E
-_0800D392:
-	movs r0, 0x80
-	lsls r0, 6
-	ands r0, r2
-	cmp r0, 0
-	beq _0800D3A0
-	movs r0, 0x4
-	b _0800D40E
-_0800D3A0:
-	movs r0, 0x80
-	lsls r0, 8
-	ands r0, r2
-	cmp r0, 0
-	beq _0800D3BA
-	lsls r1, r2, 28
-	lsrs r1, 28
-	lsls r0, r2, 20
-	lsrs r0, 28
-	cmp r1, r0
-	beq _0800D3BA
-	movs r0, 0x5
-	b _0800D40E
-_0800D3BA:
-	ldr r4, _0800D3F8
-	ldr r0, _0800D3FC
-	ldr r2, [r4]
-	ldr r0, [r0]
-	orrs r0, r2
-	movs r1, 0xE
-	ands r0, r1
-	cmp r0, 0
-	beq _0800D40C
-	ldr r0, _0800D400
-	ldr r1, [r0]
-	lsls r1, 26
-	lsrs r1, 30
-	movs r0, 0x1
-	lsls r0, r1
-	ands r2, r0
-	cmp r2, 0
-	beq _0800D40C
-	bl sub_800D1E0
-	ldr r0, [r4]
-	bl sub_800D224
-	ldr r0, [r4]
-	bl sub_800D1C0
-	lsls r0, 24
-	cmp r0, 0
-	beq _0800D404
-	movs r0, 0x2
-	b _0800D40E
-	.align 2, 0
-_0800D3F8: .4byte gUnknown_202DB68
-_0800D3FC: .4byte gUnknown_202DB6C
-_0800D400: .4byte 0x04000128
-_0800D404:
-	ldr r0, [r4]
-	bl sub_800D2EC
-	movs r5, 0x1
-_0800D40C:
-	adds r0, r5, 0
-_0800D40E:
-	pop {r4,r5}
-	pop {r1}
-	bx r1
-	thumb_func_end sub_800D33C
-
-	thumb_func_start sub_800D414
-sub_800D414:
-	push {r4,lr}
-	ldr r0, _0800D468
-	movs r4, 0
-	str r4, [r0]
-	ldr r0, _0800D46C
-	str r4, [r0]
-	ldr r0, _0800D470
-	strb r4, [r0]
-	ldr r0, _0800D474
-	str r4, [r0]
-	ldr r0, _0800D478
-	str r4, [r0]
-	str r4, [r0, 0x4]
-	ldr r0, _0800D47C
-	movs r1, 0x10
-	bl MemoryClear16
-	ldr r0, _0800D480
-	movs r1, 0x20
-	bl MemoryClear16
-	ldr r0, _0800D484
-	str r4, [r0]
-	ldr r0, _0800D488
-	str r4, [r0]
-	str r4, [r0, 0x4]
-	ldr r0, _0800D48C
-	movs r1, 0x84
-	lsls r1, 1
-	bl MemoryClear16
-	ldr r0, _0800D490
-	movs r1, 0x84
-	lsls r1, 2
-	bl MemoryClear16
-	bl sub_800D6AC
-	pop {r4}
-	pop {r0}
-	bx r0
-	.align 2, 0
-_0800D468: .4byte gUnknown_202DB68
-_0800D46C: .4byte gUnknown_202DB6C
-_0800D470: .4byte gUnknown_202DB70
-_0800D474: .4byte gUnknown_202DB74
-_0800D478: .4byte gUnknown_202DB60
-_0800D47C: .4byte gUnknown_202DB20
-_0800D480: .4byte gUnknown_202DB30
-_0800D484: .4byte gUnknown_202DB50
-_0800D488: .4byte gUnknown_202DB58
-_0800D48C: .4byte gUnknown_202D808
-_0800D490: .4byte gUnknown_202D910
-	thumb_func_end sub_800D414
-
-	thumb_func_start sub_800D494
-sub_800D494:
-	push {r4,lr}
-	ldr r0, _0800D4E4
-	movs r4, 0
-	str r4, [r0]
-	ldr r0, _0800D4E8
-	str r4, [r0]
-	ldr r0, _0800D4EC
-	strb r4, [r0]
-	ldr r0, _0800D4F0
-	str r4, [r0]
-	ldr r0, _0800D4F4
-	str r4, [r0]
-	str r4, [r0, 0x4]
-	ldr r0, _0800D4F8
-	movs r1, 0x10
-	bl MemoryClear16
-	ldr r0, _0800D4FC
-	movs r1, 0x20
-	bl MemoryClear16
-	ldr r0, _0800D500
-	str r4, [r0]
-	ldr r0, _0800D504
-	str r4, [r0]
-	str r4, [r0, 0x4]
-	ldr r0, _0800D508
-	movs r1, 0x84
-	lsls r1, 1
-	bl MemoryClear16
-	ldr r0, _0800D50C
-	movs r1, 0x84
-	lsls r1, 2
-	bl MemoryClear16
-	pop {r4}
-	pop {r0}
-	bx r0
-	.align 2, 0
-_0800D4E4: .4byte gUnknown_202DB68
-_0800D4E8: .4byte gUnknown_202DB6C
-_0800D4EC: .4byte gUnknown_202DB70
-_0800D4F0: .4byte gUnknown_202DB74
-_0800D4F4: .4byte gUnknown_202DB60
-_0800D4F8: .4byte gUnknown_202DB20
-_0800D4FC: .4byte gUnknown_202DB30
-_0800D500: .4byte gUnknown_202DB50
-_0800D504: .4byte gUnknown_202DB58
-_0800D508: .4byte gUnknown_202D808
-_0800D50C: .4byte gUnknown_202D910
-	thumb_func_end sub_800D494
-
-	thumb_func_start sub_800D510
-sub_800D510:
-	ldr r1, _0800D51C
-	movs r2, 0x80
-	lsls r2, 8
-	adds r0, r2, 0
-	strh r0, [r1]
-	bx lr
-	.align 2, 0
-_0800D51C: .4byte 0x04000134
-	thumb_func_end sub_800D510
-
-	thumb_func_start sub_800D520
-sub_800D520:
-	push {r4,r5,lr}
-	sub sp, 0x4
-	mov r1, sp
-	movs r0, 0x1
-	strh r0, [r1]
-	ldr r0, _0800D568
-	ldrb r1, [r0]
-	movs r0, 0x30
-	ands r0, r1
-	cmp r0, 0
-	bne _0800D55C
-	mov r1, sp
-	mov r0, sp
-	ldrh r0, [r0]
-	subs r0, 0x1
-	strh r0, [r1]
-	ldrh r0, [r1]
-	ldr r1, _0800D56C
-	cmp r0, r1
-	beq _0800D55C
-	mov r4, sp
-	adds r5, r1, 0
-_0800D54C:
-	bl VBlankIntrWait
-	ldrh r0, [r4]
-	subs r0, 0x1
-	strh r0, [r4]
-	ldrh r0, [r4]
-	cmp r0, r5
-	bne _0800D54C
-_0800D55C:
-	bl sub_800D7D0
-	add sp, 0x4
-	pop {r4,r5}
-	pop {r0}
-	bx r0
-	.align 2, 0
-_0800D568: .4byte 0x04000128
-_0800D56C: .4byte 0x0000ffff
-	thumb_func_end sub_800D520
-
-	thumb_func_start sub_800D570
-sub_800D570:
-	push {lr}
-	bl sub_800D7B8
-	pop {r0}
-	bx r0
-	thumb_func_end sub_800D570
-
-	thumb_func_start sub_800D57C
-sub_800D57C:
-	ldr r0, _0800D584
-	ldrb r0, [r0]
-	bx lr
-	.align 2, 0
-_0800D584: .4byte gUnknown_202DB70
-	thumb_func_end sub_800D57C
-
-	thumb_func_start sub_800D588
-sub_800D588:
-	ldr r0, _0800D598
-	ldr r0, [r0]
-	movs r1, 0x80
-	ands r0, r1
-	lsls r0, 24
-	lsrs r0, 24
-	bx lr
-	.align 2, 0
-_0800D598: .4byte gUnknown_202DB68
-	thumb_func_end sub_800D588
-
-	thumb_func_start sub_800D59C
-sub_800D59C:
-	push {r4-r6,lr}
-	adds r3, r0, 0
-	adds r2, r1, 0
-	movs r5, 0
-	ldr r6, _0800D5F4
-	ldr r4, _0800D5F8
-	adds r0, r2, 0x1
-	movs r1, 0x2
-	negs r1, r1
-	ands r0, r1
-	adds r0, 0x8
-	str r0, [r4]
-	adds r0, r6, 0x4
-	adds r1, r3, 0
-	bl CpuCopy
-	ldr r0, _0800D5FC
-	strh r0, [r6]
-	strh r5, [r6, 0x2]
-	movs r2, 0
-	ldr r0, [r4]
-	lsrs r0, 1
-	subs r0, 0x2
-	cmp r5, r0
-	bcs _0800D5DE
-	adds r3, r0, 0
-	adds r1, r6, 0
-_0800D5D2:
-	ldrh r0, [r1]
-	adds r5, r0
-	adds r1, 0x2
-	adds r2, 0x1
-	cmp r2, r3
-	bcc _0800D5D2
-_0800D5DE:
-	ldr r2, _0800D5F4
-	mvns r1, r5
-	ldr r0, _0800D5F8
-	ldr r0, [r0]
-	lsrs r0, 1
-	subs r1, r0
-	strh r1, [r2, 0x2]
-	pop {r4-r6}
-	pop {r0}
-	bx r0
-	.align 2, 0
-_0800D5F4: .4byte gUnknown_202D808
-_0800D5F8: .4byte gUnknown_202DB74
-_0800D5FC: .4byte 0x0000fdfd
-	thumb_func_end sub_800D59C
 
 	thumb_func_start sub_800D600
 sub_800D600:
diff --git a/src/code_800D090.c b/src/code_800D090.c
index b81f9c73e..8c1526501 100644
--- a/src/code_800D090.c
+++ b/src/code_800D090.c
@@ -1,5 +1,7 @@
 #include "global.h"
 #include "music.h"
+#include "memory.h"
+#include "cpu.h"
 
 extern u32 gUnknown_202DB60[2];
 extern u16 gUnknown_202DB30[2][8];
@@ -113,13 +115,13 @@ void nullsub_187(void)
 {
 }
 
-u32 sub_800D1C0(void)
+bool8 sub_800D1C0(u32 unused)
 {
     if(gUnknown_202DB60[0] != 2)
-        return 0;
+        return FALSE;
     if(gUnknown_202DB60[1] != 2)
-        return 0;
-    return 1;
+        return FALSE;
+    return TRUE;
 }
 
 void sub_800D1E0(void)
@@ -137,3 +139,188 @@ void sub_800D1E0(void)
         }
     }
 }
+
+extern u32 gUnknown_202DB58[2];
+extern u32 gUnknown_202DB74;
+extern u32 gUnknown_202DB50;
+extern u16 gUnknown_202DB208[];
+extern u16 gUnknown_202D808[132];
+extern u16 gUnknown_202D910[2][132];
+extern u16 gUnknown_202DB30[2][8];
+extern u16 gUnknown_202DB20[8];
+
+void sub_800D224(s32 a0)
+{
+    s32 i;
+
+    for (i = 0; i < 2; i++) {
+        if (((a0 >> i) & 1) && gUnknown_202DB60[i] == 1) {
+            u32 j;
+            u16 *ptr = gUnknown_202D910[i];
+
+            for (j = 0; j < 8; j++) {
+                if (gUnknown_202DB58[i] + j >= gUnknown_202DB74 / 2) {
+                    gUnknown_202DB60[i] = 2;
+                    break;
+                }
+                ptr[gUnknown_202DB58[i] + j] = gUnknown_202DB30[i][j];
+            }
+
+            gUnknown_202DB58[i] += 8;
+        }
+    }
+}
+
+void sub_800D2EC(u32 unused)
+{
+    u32 i;
+    u16 *ptr = gUnknown_202D808;
+
+    for (i = 0; i < 8; i++) {
+        if (gUnknown_202DB50 < (gUnknown_202DB74 / 2)) {
+            gUnknown_202DB20[i] = ptr[gUnknown_202DB50++];
+        }
+        else {
+            gUnknown_202DB20[i] = 0xFCFC;
+        }
+    }
+}
+
+extern u32 gUnknown_202DB68;
+extern s32 gUnknown_202DB6C;
+extern u8 gUnknown_202DB70;
+
+u32 sub_800D820(u16 *a0, u16 *a1);
+
+s32 sub_800D33C(void)
+{
+    s32 ret = 0;
+
+    gUnknown_202DB6C = gUnknown_202DB68;
+    gUnknown_202DB68 = sub_800D820(gUnknown_202DB20, gUnknown_202DB30[0]);
+    if (gUnknown_202DB70 == 0) {
+        if (gUnknown_202DB68 & 0x100) {
+            gUnknown_202DB70 = 1;
+        }
+        return 0;
+    }
+    else if (gUnknown_202DB68 & 0x1000) {
+        return 3;
+    }
+    else if (gUnknown_202DB68 & 0x2000) {
+        return 4;
+    }
+    else if (gUnknown_202DB68 & 0x8000) {
+        u32 bits1, bits2;
+
+        bits1 = gUnknown_202DB68 << 28;
+        bits1 >>= 28;
+
+        bits2 = gUnknown_202DB68 << 20;
+        bits2 >>= 28;
+        if (bits1 != bits2)
+            return 5;
+    }
+
+    if (((gUnknown_202DB68 | gUnknown_202DB6C) & 0xE)) {
+        u32 si0Cnt = (*(vu32 *)REG_ADDR_SIOCNT);
+        si0Cnt <<= 26;
+        si0Cnt >>= 30;
+        if ((gUnknown_202DB68 & (1 << si0Cnt))) {
+            sub_800D1E0();
+            sub_800D224(gUnknown_202DB68);
+            if (sub_800D1C0(gUnknown_202DB68)) {
+                return 2;
+            }
+            sub_800D2EC(gUnknown_202DB68);
+            ret = 1;
+        }
+    }
+
+    return ret;
+}
+
+void sub_800D6AC(void);
+void sub_800D7D0(void);
+void sub_800D7B8(void);
+
+static inline void ClearUnkMemory(void)
+{
+    gUnknown_202DB68 = 0;
+    gUnknown_202DB6C = 0;
+    gUnknown_202DB70 = 0;
+    gUnknown_202DB74 = 0;
+    gUnknown_202DB60[0] = 0;
+    gUnknown_202DB60[1] = 0;
+    MemoryClear16(gUnknown_202DB20, sizeof(gUnknown_202DB20));
+    MemoryClear16(gUnknown_202DB30[0], sizeof(gUnknown_202DB30));
+    gUnknown_202DB50 = 0;
+    gUnknown_202DB58[0] = 0;
+    gUnknown_202DB58[1] = 0;
+    MemoryClear16(gUnknown_202D808, sizeof(gUnknown_202D808));
+    MemoryClear16(gUnknown_202D910[0], sizeof(gUnknown_202D910));
+}
+
+// These two are the same, except sub_800D414 calls an additional func
+void sub_800D414(void)
+{
+    ClearUnkMemory();
+    sub_800D6AC();
+}
+
+void sub_800D494(void)
+{
+    ClearUnkMemory();
+}
+
+void sub_800D510(void)
+{
+    REG_RCNT = 0x8000;
+}
+
+void sub_800D520(void)
+{
+    vu16 var = 1; // Has to be u16, not s16
+    u8 si0Cnt = (*(vu8 *)REG_ADDR_SIOCNT); // First 8 bits
+
+    if (!(si0Cnt & 0x30)) {
+        while (--var != (u16) -1) {
+            VBlankIntrWait();
+        }
+    }
+    sub_800D7D0();
+}
+
+void sub_800D570()
+{
+    sub_800D7B8();
+}
+
+UNUSED static u8 sub_800D57C(void)
+{
+    return gUnknown_202DB70;
+}
+
+u8 sub_800D588(void)
+{
+    return (gUnknown_202DB68 & 0x80);
+}
+
+void sub_800D59C(u16 *src, u32 size)
+{
+    u32 i;
+    u16 bits;
+    s32 count = 0;
+    u16 *dst = gUnknown_202D808;
+
+    gUnknown_202DB74 = ((size + 1) & ~(1)) + 8;
+    CpuCopy(&dst[2], src, size);
+    bits = 0xFDFD;
+    dst[0] = bits;
+    dst[1] = 0;
+    for (i = 0; i < (gUnknown_202DB74 / 2) - 2; i++) {
+        count += dst[i];
+    }
+
+    gUnknown_202D808[1] = ~count - (gUnknown_202DB74 / 2);
+}