diff --git a/asm/include/main_0205BD40.inc b/asm/include/main_0205BD5C.inc
similarity index 99%
rename from asm/include/main_0205BD40.inc
rename to asm/include/main_0205BD5C.inc
index 3dedb683..c32746fa 100644
--- a/asm/include/main_0205BD40.inc
+++ b/asm/include/main_0205BD5C.inc
@@ -385,4 +385,5 @@
 .public sub_02059AF8
 .public sub_0205B44C
 .public sub_0205B77C
+.public sub_0205BD40
 .public vsprintf
diff --git a/asm/main_0205BD40.s b/asm/main_0205BD5C.s
similarity index 99%
rename from asm/main_0205BD40.s
rename to asm/main_0205BD5C.s
index 45ca9627..b3b96453 100644
--- a/asm/main_0205BD40.s
+++ b/asm/main_0205BD5C.s
@@ -1,19 +1,8 @@
 	.include "asm/macros.inc"
-	.include "main_0205BD40.inc"
+	.include "main_0205BD5C.inc"
 
 	.text
 
-	arm_func_start sub_0205BD40
-sub_0205BD40: ; 0x0205BD40
-	tst r0, #2
-	movne r0, #0
-	bxne lr
-	tst r0, #1
-	movne r0, #2
-	moveq r0, #1
-	bx lr
-	arm_func_end sub_0205BD40
-
 	arm_func_start sub_0205BD5C
 sub_0205BD5C: ; 0x0205BD5C
 	stmdb sp!, {r3, lr}
diff --git a/include/main_0205BD14.h b/include/main_0205BD14.h
index c9283f59..3cabdc34 100644
--- a/include/main_0205BD14.h
+++ b/include/main_0205BD14.h
@@ -2,5 +2,6 @@
 #define PMDSKY_MAIN_0205BD14_H
 
 void sub_0205BD14(u32 *dest, s32 index);
+u32 sub_0205BD40(u32 val);
 
 #endif //PMDSKY_MAIN_0205BD14_H
diff --git a/main.lsf b/main.lsf
index 35879219..982fca14 100644
--- a/main.lsf
+++ b/main.lsf
@@ -158,7 +158,7 @@ Static main
 	Object src/main_0205BBFC.o
 	Object asm/main_0205BCC4.o
 	Object src/main_0205BD14.o
-	Object asm/main_0205BD40.o
+	Object asm/main_0205BD5C.o
 	Object src/dungeon_init_2.o
 	Object asm/main_0206A750.o
 	Object src/main_0206C98C.o
diff --git a/src/main_0205BD14.c b/src/main_0205BD14.c
index 705f8403..dcdbce02 100644
--- a/src/main_0205BD14.c
+++ b/src/main_0205BD14.c
@@ -3,9 +3,17 @@
 
 extern union unkStruct_020B0A54_union _020B0A54;
 
-extern u32 sub_0205BD40(u32 param);
-
 void sub_0205BD14(u32 *dest, s32 index)
 {
     *dest = sub_0205BD40(_020B0A54.struct0[index].unkAE);
 }
+
+u32 sub_0205BD40(u32 val)
+{
+    if (val & 2)
+    {
+        return 0;
+    }
+
+    return val & 1 ? 2 : 1;
+}