diff --git a/asm/include/main_02054AD4.inc b/asm/include/main_02054AD4.inc
deleted file mode 100644
index 3f59c932..00000000
--- a/asm/include/main_02054AD4.inc
+++ /dev/null
@@ -1,2 +0,0 @@
-#pragma once
-
diff --git a/asm/main_02054AD4.s b/asm/main_02054AD4.s
deleted file mode 100644
index 2139c3b7..00000000
--- a/asm/main_02054AD4.s
+++ /dev/null
@@ -1,59 +0,0 @@
-	.include "asm/macros.inc"
-	.include "main_02054AD4.inc"
-
-	.text
-
-	arm_func_start IsCastform
-IsCastform: ; 0x02054AD4
-	ldr r2, _02054B24 ; =0x0000017B
-	cmp r0, r2
-	cmpne r0, #0x17c
-	addne r1, r2, #2
-	cmpne r0, r1
-	addne r1, r2, #3
-	cmpne r0, r1
-	beq _02054B14
-	ldr r1, _02054B28 ; =0xFFFFFC2D
-	add r0, r0, r1
-	mov r0, r0, lsl #0x10
-	mov r0, r0, asr #0x10
-	mov r0, r0, lsl #0x10
-	mov r0, r0, lsr #0x10
-	cmp r0, #3
-	bhi _02054B1C
-_02054B14:
-	mov r0, #1
-	bx lr
-_02054B1C:
-	mov r0, #0
-	bx lr
-	.align 2, 0
-_02054B24: .word 0x0000017B
-_02054B28: .word 0xFFFFFC2D
-	arm_func_end IsCastform
-
-	arm_func_start IsCherrim
-IsCherrim: ; 0x02054B2C
-	cmp r0, #0x1cc
-	ldrne r1, _02054B6C ; =0x000001CD
-	cmpne r0, r1
-	beq _02054B5C
-	ldr r1, _02054B70 ; =0xFFFFFBDC
-	add r0, r0, r1
-	mov r0, r0, lsl #0x10
-	mov r0, r0, asr #0x10
-	mov r0, r0, lsl #0x10
-	mov r0, r0, lsr #0x10
-	cmp r0, #1
-	bhi _02054B64
-_02054B5C:
-	mov r0, #1
-	bx lr
-_02054B64:
-	mov r0, #0
-	bx lr
-	.align 2, 0
-_02054B6C: .word 0x000001CD
-_02054B70: .word 0xFFFFFBDC
-	arm_func_end IsCherrim
-
diff --git a/include/main_02054AA4.h b/include/main_02054AA4.h
index 53404f8a..0a28576b 100644
--- a/include/main_02054AA4.h
+++ b/include/main_02054AA4.h
@@ -1,9 +1,12 @@
 #ifndef PMDSKY_MAIN_02054AA4_H
 #define PMDSKY_MAIN_02054AA4_H
 
+#include "enums.h"
 #include "util.h"
 
 bool8 IsUnown(s16 monster_id);
 bool8 IsShaymin(s16 monster_id);
+bool8 IsCastform(enum monster_id monster_id);
+bool8 IsCherrim(enum monster_id monster_id);
 
 #endif //PMDSKY_MAIN_02054AA4_H
diff --git a/main.lsf b/main.lsf
index 036ca900..371ee3df 100644
--- a/main.lsf
+++ b/main.lsf
@@ -149,7 +149,6 @@ Static main
 	Object src/main_02052B28.o
 	Object asm/main_02052B44.o
 	Object src/main_02054AA4.o
-	Object asm/main_02054AD4.o
 	Object src/main_02054BE0.o
 	Object src/main_02054C24.o
 	Object src/main_02054DC4.o
diff --git a/src/main_02054AA4.c b/src/main_02054AA4.c
index 7120ff07..4282b208 100644
--- a/src/main_02054AA4.c
+++ b/src/main_02054AA4.c
@@ -10,3 +10,28 @@ bool8 IsUnown(s16 monster_id) {
 bool8 IsShaymin(s16 monster_id) {
     return (u16)(s16)(monster_id - MONSTER_SHAYMIN_LAND) <= 1;
 }
+
+bool8 IsCastform(enum monster_id monster_id)
+{
+    if(monster_id == MONSTER_CASTFORM_NORMAL ||
+       monster_id == MONSTER_CASTFORM_SNOWY ||
+       monster_id == MONSTER_CASTFORM_SUNNY || 
+       monster_id == MONSTER_CASTFORM_RAINY ||
+       ((u16)(s16)(monster_id - MONSTER_CASTFORM_NORMAL_SECONDARY) <= 3)
+    ) {
+       return TRUE;
+    }
+    
+    return FALSE;
+}
+
+bool8 IsCherrim(enum monster_id monster_id)
+{
+    if (monster_id == MONSTER_CHERRIM_OVERCAST || 
+        monster_id == MONSTER_CHERRIM_SUNSHINE || 
+        ((u16)(s16)(monster_id - MONSTER_CHERRIM_OVERCAST_SECONDARY) <= 1)) {
+        return TRUE;
+    }
+    
+    return FALSE;
+}