diff --git a/include/ability.h b/include/ability.h
index 071b3ae..7d389e8 100644
--- a/include/ability.h
+++ b/include/ability.h
@@ -3,6 +3,7 @@
 
 #include <ultra64.h>
 
+#include "ability_id.h"
 #include "assert.h"
 #include "element.h"
 #include "equipment_id.h"
@@ -27,9 +28,10 @@ ASSERT_SIZE(AbilityData, 0x10);
 
 extern AbilityData obAbilityData[];
 
-extern char *obAbilityGetName(u8 index);
-extern u8 ability_get_field_0x4(u8 index);
-extern Element obAbilityGetElement(u8 index, EquipmentId arg1, EquipmentId arg2,
-                                   EquipmentId arg3, EquipmentId arg4);
+extern char *obAbilityGetName(AbilityId index);
+extern u8 ability_get_field_0x4(AbilityId index);
+extern Element obAbilityGetElement(AbilityId index, EquipmentId arg1,
+                                   EquipmentId arg2, EquipmentId arg3,
+                                   EquipmentId arg4);
 
 #endif // __ABILITY_H__
\ No newline at end of file
diff --git a/include/ability_id.h b/include/ability_id.h
new file mode 100644
index 0000000..fb0de83
--- /dev/null
+++ b/include/ability_id.h
@@ -0,0 +1,27 @@
+#ifndef __ABILITY_ID_H__
+#define __ABILITY_ID_H__
+
+#include <ultratypes.h>
+
+typedef u8 AbilityId;
+
+#define ABILITY_ID_THRUST 1
+#define ABILITY_ID_PECK 2
+#define ABILITY_ID_PIERCE 3
+#define ABILITY_ID_SLASH 4
+#define ABILITY_ID_CLEAVE 5
+#define ABILITY_ID_REND 6
+#define ABILITY_ID_CLAW 7
+#define ABILITY_ID_BITE 8
+#define ABILITY_ID_STRIKE 9
+#define ABILITY_ID_CRUSH 10
+#define ABILITY_ID_SMASH 11
+#define ABILITY_ID_LASH 12
+#define ABILITY_ID_PULL_STRINGS 13
+#define ABILITY_ID_SHOOT 14
+#define ABILITY_ID_TAKE_A_PEEK 15
+#define ABILITY_ID_FLIP_OVER 16
+#define ABILITY_ID_SONIC_BOOM 17
+#define ABILITY_ID_WIND_SHOT 17
+
+#endif // __ABILITY_ID_H__
\ No newline at end of file
diff --git a/src/segment_obdata/_ob_fierce_selection.c b/src/segment_obdata/_ob_fierce_selection.c
index 655f3ea..260504b 100644
--- a/src/segment_obdata/_ob_fierce_selection.c
+++ b/src/segment_obdata/_ob_fierce_selection.c
@@ -196,15 +196,15 @@ EquipmentId obClassGetItemLowerRight(u8 portrait, ClassId class) {
 
 /* 43FD8 8016E0D8 */
 char* obClassGetAbilityFrontName(u8 portrait, ClassId class) {
-    u8 var_v0;
+    AbilityId ability;
 
     if (obClassData[portrait].field_0x45 == class) {
-        var_v0 = obClassData[portrait].ability_front;
+        ability = obClassData[portrait].ability_front;
     } else {
-        var_v0 = obClassData[class].ability_front;
+        ability = obClassData[class].ability_front;
     }
     
-    return obAbilityGetName(var_v0);
+    return obAbilityGetName(ability);
 }
 
 /* 44040 8016E140 */
@@ -218,15 +218,15 @@ char* obClassGetAbilityMiddleName(u8 portrait, ClassId class) {
 
 /* 44074 8016E174 */
 char* obClassGetAbilityBackName(u8 portrait, ClassId class) {
-    u8 var_v0;
+    AbilityId ability;
 
     if (obClassData[portrait].field_0x45 == class) {
-        var_v0 = obClassData[portrait].ability_back;
+        ability = obClassData[portrait].ability_back;
     } else {
-        var_v0 = obClassData[class].ability_back;
+        ability = obClassData[class].ability_back;
     }
     
-    return obAbilityGetName(var_v0);
+    return obAbilityGetName(ability);
 }
 
 /* 440DC 8016E1DC */
@@ -267,17 +267,17 @@ u8 obClassGetAbilityHits(u8 portrait, ClassId class, u8 row) {
 }
 
 /* 44340 8016E440 */
-char* obAbilityGetName(u8 index) {
+char* obAbilityGetName(AbilityId index) {
     return obAbilityData[index].name;
 }
 
 /* 44358 8016E458 */
-u8 ability_get_field_0x4(u8 index) {
+u8 ability_get_field_0x4(AbilityId index) {
     return obAbilityData[index].field_0x4;
 }
 
 /* 44370 8016E470 */
-Element obAbilityGetElement(u8 index, EquipmentId arg1, EquipmentId arg2, EquipmentId arg3, EquipmentId arg4) {
+Element obAbilityGetElement(AbilityId index, EquipmentId arg1, EquipmentId arg2, EquipmentId arg3, EquipmentId arg4) {
     u16 item_index;    
     
     if (obAbilityData[index].element != ELEMENT_INVALID && obAbilityData[index].element != 0xF)