diff --git a/constants/pokemon_data_constants.asm b/constants/pokemon_data_constants.asm
index 0eb4a79ae9d..fcab511588e 100644
--- a/constants/pokemon_data_constants.asm
+++ b/constants/pokemon_data_constants.asm
@@ -77,7 +77,7 @@ rsreset
 DEF MON_SPECIES            rb
 DEF MON_ITEM               rb
 DEF MON_MOVES              rb NUM_MOVES
-DEF MON_OT_ID              rw
+DEF MON_ID                 rw
 DEF MON_EXP                rb 3
 DEF MON_STAT_EXP           rw NUM_EXP_STATS
 rsset MON_STAT_EXP
diff --git a/engine/battle/core.asm b/engine/battle/core.asm
index b8cd5408336..6e15a0fc2c8 100644
--- a/engine/battle/core.asm
+++ b/engine/battle/core.asm
@@ -3892,9 +3892,9 @@ InitBattleMon:
 	ld a, MON_SPECIES
 	call GetPartyParamLocation
 	ld de, wBattleMonSpecies
-	ld bc, MON_OT_ID
+	ld bc, MON_ID
 	call CopyBytes
-	ld bc, MON_DVS - MON_OT_ID
+	ld bc, MON_DVS - MON_ID
 	add hl, bc
 	ld de, wBattleMonDVs
 	ld bc, MON_POKERUS - MON_DVS
@@ -3978,9 +3978,9 @@ InitEnemyMon:
 	ld hl, wOTPartyMon1Species
 	call GetPartyLocation
 	ld de, wEnemyMonSpecies
-	ld bc, MON_OT_ID
+	ld bc, MON_ID
 	call CopyBytes
-	ld bc, MON_DVS - MON_OT_ID
+	ld bc, MON_DVS - MON_ID
 	add hl, bc
 	ld de, wEnemyMonDVs
 	ld bc, MON_POKERUS - MON_DVS
@@ -7124,7 +7124,7 @@ GiveExperiencePoints:
 	call Divide
 ; Boost Experience for traded Pokemon
 	pop bc
-	ld hl, MON_OT_ID
+	ld hl, MON_ID
 	add hl, bc
 	ld a, [wPlayerID]
 	cp [hl]
diff --git a/engine/battle/effect_commands.asm b/engine/battle/effect_commands.asm
index 62ea56f5818..97631749f49 100644
--- a/engine/battle/effect_commands.asm
+++ b/engine/battle/effect_commands.asm
@@ -655,9 +655,9 @@ BattleCommand_CheckObedience:
 	and a
 	ret nz
 
-	; If the Pokémon's Trainer ID doesn't match the player's,
+	; If the monster's id doesn't match the player's,
 	; some conditions need to be met.
-	ld a, MON_OT_ID
+	ld a, MON_ID
 	call BattlePartyAttr
 
 	ld a, [wPlayerID]
diff --git a/engine/events/daycare.asm b/engine/events/daycare.asm
index ec386185f4a..00675502b0e 100644
--- a/engine/events/daycare.asm
+++ b/engine/events/daycare.asm
@@ -491,7 +491,7 @@ DayCare_GiveEgg:
 	call AddNTimes
 	ld b, h
 	ld c, l
-	ld hl, MON_OT_ID + 1
+	ld hl, MON_ID + 1
 	add hl, bc
 	push hl
 	ld hl, MON_MAXHP
diff --git a/engine/events/halloffame.asm b/engine/events/halloffame.asm
index 21b6f866bd3..ed7ae6c7051 100644
--- a/engine/events/halloffame.asm
+++ b/engine/events/halloffame.asm
@@ -171,7 +171,7 @@ GetHallOfFameParty:
 	ld [de], a
 	inc de
 
-	ld hl, MON_OT_ID
+	ld hl, MON_ID
 	add hl, bc
 	ld a, [hli]
 	ld [de], a
diff --git a/engine/events/lucky_number.asm b/engine/events/lucky_number.asm
index 46f073c2bdd..375b817b84f 100644
--- a/engine/events/lucky_number.asm
+++ b/engine/events/lucky_number.asm
@@ -149,7 +149,7 @@ CheckForLuckyNumberWinners:
 .done
 	pop hl
 	push hl
-	ld de, MON_SPECIES - MON_OT_ID
+	ld de, MON_SPECIES - MON_ID
 	add hl, de
 	ld a, [hl]
 	pop hl
diff --git a/engine/events/magikarp.asm b/engine/events/magikarp.asm
index 0c0ba87bba4..7fbec56beb4 100644
--- a/engine/events/magikarp.asm
+++ b/engine/events/magikarp.asm
@@ -11,7 +11,7 @@ CheckMagikarpLength:
 	cp MAGIKARP
 	jr nz, .not_magikarp
 
-	; Now let's compute its length based on its DVs and Trainer ID.
+	; Now let's compute its length based on its DVs and ID.
 	ld a, [wCurPartyMon]
 	ld hl, wPartyMon1Species
 	ld bc, PARTYMON_STRUCT_LENGTH
@@ -22,7 +22,7 @@ CheckMagikarpLength:
 	ld d, h
 	ld e, l
 	pop hl
-	ld bc, MON_OT_ID
+	ld bc, MON_ID
 	add hl, bc
 	ld b, h
 	ld c, l
diff --git a/engine/events/poke_seer.asm b/engine/events/poke_seer.asm
index 744f2083af7..b3b971814b5 100644
--- a/engine/events/poke_seer.asm
+++ b/engine/events/poke_seer.asm
@@ -114,7 +114,7 @@ ReadCaughtData:
 	ld a, SEERACTION_TRADED
 	ld [wSeerAction], a
 
-	ld a, MON_OT_ID
+	ld a, MON_ID
 	call GetPartyParamLocation
 	ld a, [wPlayerID]
 	cp [hl]
diff --git a/engine/pokemon/breeding.asm b/engine/pokemon/breeding.asm
index d10361f8945..a2c25112e4d 100644
--- a/engine/pokemon/breeding.asm
+++ b/engine/pokemon/breeding.asm
@@ -296,7 +296,7 @@ HatchEggs:
 	ld [hli], a
 	ld a, [de]
 	ld [hl], a
-	ld hl, MON_OT_ID
+	ld hl, MON_ID
 	add hl, bc
 	ld a, [wPlayerID]
 	ld [hli], a
diff --git a/engine/pokemon/search_owned.asm b/engine/pokemon/search_owned.asm
index 9854a24c596..c1426b9e373 100644
--- a/engine/pokemon/search_owned.asm
+++ b/engine/pokemon/search_owned.asm
@@ -200,7 +200,7 @@ CheckOwnMon:
 ; wScriptVar should contain the species we're looking for
 
 ; outputs:
-; sets carry if monster matches species, Trainer ID, and OT name.
+; sets carry if monster matches species, ID, and OT name.
 
 	push bc
 	push hl
@@ -215,9 +215,9 @@ CheckOwnMon:
 	cp b
 	jr nz, .notfound
 
-	; check Trainer ID number
+	; check ID number
 
-	ld bc, MON_OT_ID
+	ld bc, MON_ID
 	add hl, bc
 	ld a, [wPlayerID]
 	cp [hl]