diff --git a/include/mon_markings.h b/include/mon_markings.h
index 8e4ec58bd..241b31e01 100644
--- a/include/mon_markings.h
+++ b/include/mon_markings.h
@@ -1,17 +1,19 @@
 #ifndef POKEEMERALD_MON_MARKINGS_H
 #define POKEEMERALD_MON_MARKINGS_H
 
+#define NUM_MON_MARKINGS 4
+
 struct PokemonMarkMenu
 {
     /*0x0000*/ u16 baseTileTag;
     /*0x0002*/ u16 basePaletteTag;
     /*0x0004*/ u8 markings; // bit flags
     /*0x0005*/ s8 cursorPos;
-    /*0x0006*/ bool8 markingsArray[4];
+    /*0x0006*/ bool8 markingsArray[NUM_MON_MARKINGS];
     /*0x000A*/ u8 cursorBaseY;
     /*0x000B*/ bool8 spriteSheetLoadRequired;
     /*0x000C*/ struct Sprite *menuWindowSprites[2]; // upper and lower halves of menu window
-    /*0x0014*/ struct Sprite *menuMarkingSprites[4];
+    /*0x0014*/ struct Sprite *menuMarkingSprites[NUM_MON_MARKINGS];
     /*0x0024*/ struct Sprite *unkSprite;
     /*0x0028*/ struct Sprite *menuTextSprite;
     /*0x002C*/ const u8 *frameTiles;
diff --git a/src/battle_ai_script_commands.c b/src/battle_ai_script_commands.c
index 6a8163b96..b581a8bbc 100644
--- a/src/battle_ai_script_commands.c
+++ b/src/battle_ai_script_commands.c
@@ -298,7 +298,7 @@ void BattleAI_HandleItemUseBeforeAISetup(u8 defaultScoreMoves)
             )
        )
     {
-        for (i = 0; i < 4; i++)
+        for (i = 0; i < MAX_TRAINER_ITEMS; i++)
         {
             if (gTrainers[gTrainerBattleOpponent_A].items[i] != 0)
             {
diff --git a/src/battle_ai_switch_items.c b/src/battle_ai_switch_items.c
index cd31293f8..6ef359150 100644
--- a/src/battle_ai_switch_items.c
+++ b/src/battle_ai_switch_items.c
@@ -820,7 +820,7 @@ static bool8 ShouldUseItem(void)
         }
     }
 
-    for (i = 0; i < 4; i++)
+    for (i = 0; i < MAX_TRAINER_ITEMS; i++)
     {
         u16 item;
         const u8 *itemEffects;
diff --git a/src/battle_main.c b/src/battle_main.c
index 87e29dd57..27889e81e 100644
--- a/src/battle_main.c
+++ b/src/battle_main.c
@@ -1790,9 +1790,9 @@ static void CB2_HandleStartMultiBattle(void)
         gBattleCommunication[SPRITES_INIT_STATE2] = 0;
         if (gBattleTypeFlags & BATTLE_TYPE_LINK)
         {
-            for (id = 0; id < 4 && (gLinkPlayers[id].version & 0xFF) == 3; id++);
+            for (id = 0; id < MAX_LINK_PLAYERS && (gLinkPlayers[id].version & 0xFF) == VERSION_EMERALD; id++);
 
-            if (id == 4)
+            if (id == MAX_LINK_PLAYERS)
                 gBattleCommunication[MULTIUSE_STATE] = 8;
             else
                 gBattleCommunication[MULTIUSE_STATE] = 10;
@@ -4244,7 +4244,7 @@ static void HandleTurnActionSelectionState(void)
                         moveInfo.monType1 = gBattleMons[gActiveBattler].type1;
                         moveInfo.monType2 = gBattleMons[gActiveBattler].type2;
 
-                        for (i = 0; i < 4; i++)
+                        for (i = 0; i < MAX_MON_MOVES; i++)
                         {
                             moveInfo.moves[i] = gBattleMons[gActiveBattler].moves[i];
                             moveInfo.currentPp[i] = gBattleMons[gActiveBattler].pp[i];
diff --git a/src/battle_script_commands.c b/src/battle_script_commands.c
index 5016a3a58..6f1b43240 100644
--- a/src/battle_script_commands.c
+++ b/src/battle_script_commands.c
@@ -10184,7 +10184,7 @@ static void atkEF_handleballthrow(void)
             gBattlescriptCurrInstr = BattleScript_SuccessBallThrow;
             SetMonData(&gEnemyParty[gBattlerPartyIndexes[gBattlerTarget]], MON_DATA_POKEBALL, &gLastUsedItem);
 
-            if (CalculatePlayerPartyCount() == 6)
+            if (CalculatePlayerPartyCount() == PARTY_SIZE)
                 gBattleCommunication[MULTISTRING_CHOOSER] = 0;
             else
                 gBattleCommunication[MULTISTRING_CHOOSER] = 1;
@@ -10196,7 +10196,7 @@ static void atkEF_handleballthrow(void)
             odds = Sqrt(Sqrt(16711680 / odds));
             odds = 1048560 / odds;
 
-            for (shakes = 0; shakes < 4 && Random() < odds; shakes++);
+            for (shakes = 0; shakes < BALL_3_SHAKES_SUCCESS && Random() < odds; shakes++);
 
             if (gLastUsedItem == ITEM_MASTER_BALL)
                 shakes = BALL_3_SHAKES_SUCCESS; // why calculate the shakes before that check?
@@ -10209,7 +10209,7 @@ static void atkEF_handleballthrow(void)
                 gBattlescriptCurrInstr = BattleScript_SuccessBallThrow;
                 SetMonData(&gEnemyParty[gBattlerPartyIndexes[gBattlerTarget]], MON_DATA_POKEBALL, &gLastUsedItem);
 
-                if (CalculatePlayerPartyCount() == 6)
+                if (CalculatePlayerPartyCount() == PARTY_SIZE)
                     gBattleCommunication[MULTISTRING_CHOOSER] = 0;
                 else
                     gBattleCommunication[MULTISTRING_CHOOSER] = 1;
diff --git a/src/mon_markings.c b/src/mon_markings.c
index f8b128045..f4d6b3818 100644
--- a/src/mon_markings.c
+++ b/src/mon_markings.c
@@ -350,7 +350,7 @@ void sub_811FAA4(u8 markings, s16 x, s16 y)
     u16 i;
     sMenu->cursorPos = 0;
     sMenu->markings = markings;
-    for (i = 0; i < 4; i++)
+    for (i = 0; i < NUM_MON_MARKINGS; i++)
         sMenu->markingsArray[i] = (sMenu->markings >> i) & 1;
     sub_811FC80(x, y, sMenu->baseTileTag, sMenu->basePaletteTag);
 }
@@ -371,7 +371,7 @@ void sub_811FAF8(void)
         DestroySprite(sMenu->menuWindowSprites[i]);
         sMenu->menuWindowSprites[i] = NULL;
     }
-    for (i = 0; i < 4; i++)
+    for (i = 0; i < NUM_MON_MARKINGS; i++)
     {
         if (!sMenu->menuMarkingSprites[i])
             return;
@@ -422,7 +422,7 @@ bool8 sub_811FBA4(void)
         {
         case 4:
             sMenu->markings = 0;
-            for (i = 0; i < 4; i++)
+            for (i = 0; i < NUM_MON_MARKINGS; i++)
                 sMenu->markings |= sMenu->markingsArray[i] << i;
             return FALSE;
         case 5:
@@ -498,7 +498,7 @@ static void sub_811FC80(s16 x, s16 y, u16 baseTileTag, u16 basePaletteTag)
     sprTemplate.callback = sub_811FF40;
     sprTemplate.oam = &gUnknown_0859EE84;
 
-    for (i = 0; i < 4; i++)
+    for (i = 0; i < NUM_MON_MARKINGS; i++)
     {
         spriteId = CreateSprite(&sprTemplate, x + 32, y + 16 + 16 * i, 0);
         if (spriteId != MAX_SPRITES)
diff --git a/src/new_game.c b/src/new_game.c
index b4d9ba9b3..1021ea96c 100644
--- a/src/new_game.c
+++ b/src/new_game.c
@@ -81,7 +81,7 @@ u32 GetTrainerId(u8 *trainerId)
 void CopyTrainerId(u8 *dst, u8 *src)
 {
     s32 i;
-    for (i = 0; i < 4; i++)
+    for (i = 0; i < TRAINER_ID_LENGTH; i++)
         dst[i] = src[i];
 }
 
diff --git a/src/overworld.c b/src/overworld.c
index cefbd8159..51d9ad9b5 100644
--- a/src/overworld.c
+++ b/src/overworld.c
@@ -2435,7 +2435,7 @@ static void UpdateAllLinkPlayers(u16 *keys, s32 selfId)
     struct TradeRoomPlayer trainer;
     s32 i;
 
-    for (i = 0; i < 4; i++)
+    for (i = 0; i < MAX_LINK_PLAYERS; i++)
     {
         u8 key = keys[i];
         u16 setFacing = FACING_NONE;
@@ -3026,7 +3026,7 @@ static s32 sub_80878E4(u8 linkPlayerId)
 static u8 GetLinkPlayerIdAt(s16 x, s16 y)
 {
     u8 i;
-    for (i = 0; i < 4; i++)
+    for (i = 0; i < MAX_LINK_PLAYERS; i++)
     {
         if (gLinkPlayerEventObjects[i].active
          && (gLinkPlayerEventObjects[i].movementMode == 0 || gLinkPlayerEventObjects[i].movementMode == 2))
diff --git a/src/pokemon.c b/src/pokemon.c
index a393759d3..4833f2db6 100644
--- a/src/pokemon.c
+++ b/src/pokemon.c
@@ -6683,7 +6683,7 @@ u8 sub_806EF08(u8 arg0)
         var = (arg0 != 0) ? 2 : 0;
         break;
     }
-    for (i = 0; i < 4; i++)
+    for (i = 0; i < MAX_LINK_PLAYERS; i++)
     {
         if (gLinkPlayers[i].id == (s16)(var))
             break;
@@ -6706,7 +6706,7 @@ u8 sub_806EF84(u8 arg0, u8 arg1)
         var = (arg0 != 0) ? 2 : 0;
         break;
     }
-    for (i = 0; i < 4; i++)
+    for (i = 0; i < MAX_LINK_PLAYERS; i++)
     {
         if (gLinkPlayers[i].id == (s16)(var))
             break;