diff --git a/asm/field_map_obj.s b/asm/field_map_obj.s
index ccd56427c..6fd4e2005 100644
--- a/asm/field_map_obj.s
+++ b/asm/field_map_obj.s
@@ -5,35 +5,6 @@
 
 	.text
 
-	thumb_func_start sub_808D4F4
-sub_808D4F4: @ 808D4F4
-	push {lr}
-	movs r1, 0
-	ldr r2, =gUnknown_02037350
-	ldrb r0, [r2]
-	b _0808D518
-	.pool
-_0808D504:
-	adds r0, r1, 0x1
-	lsls r0, 24
-	lsrs r1, r0, 24
-	cmp r1, 0xF
-	bhi _0808D51E
-	lsls r0, r1, 3
-	adds r0, r1
-	lsls r0, 2
-	adds r0, r2
-	ldrb r0, [r0]
-_0808D518:
-	lsls r0, 31
-	cmp r0, 0
-	bne _0808D504
-_0808D51E:
-	adds r0, r1, 0
-	pop {r1}
-	bx r1
-	thumb_func_end sub_808D4F4
-
 	thumb_func_start GetFieldObjectIdByLocalIdAndMap
 @ u8 GetFieldObjectIdByLocalIdAndMap(u8 localId, u8 mapId, u8 mapGroupId)
 GetFieldObjectIdByLocalIdAndMap: @ 808D524
diff --git a/src/field_map_obj.c b/src/field_map_obj.c
index 7b5731e68..46cc0585c 100644
--- a/src/field_map_obj.c
+++ b/src/field_map_obj.c
@@ -30,6 +30,7 @@
 static void npcs_clear_ids_and_state(void)
 {
     u8 i;
+
     for (i = 0; i < ARRAY_COUNT(gUnknown_02037350); i ++)
     {
         npc_clear_ids_and_state(&gUnknown_02037350[i]);
@@ -60,3 +61,17 @@ void sub_808D438(void)
     StartSpriteAffineAnim(&gSprites[spriteIdx], 1);
     gSprites[spriteIdx].invisible = TRUE;
 }
+
+u8 sub_808D4F4(void)
+{
+    u8 i;
+
+    for (i = 0; i < ARRAY_COUNT(gUnknown_02037350); i ++)
+    {
+        if (!gUnknown_02037350[i].active)
+        {
+            break;
+        }
+    }
+    return i;
+}