diff --git a/src/battle_anim_dark.c b/src/battle_anim_dark.c
index a063af66d..1281ccc8b 100644
--- a/src/battle_anim_dark.c
+++ b/src/battle_anim_dark.c
@@ -426,7 +426,7 @@ void AnimTask_MoveAttackerMementoShadow(u8 taskId)
         GetBattleAnimBg1Data(&animBg);
         task->data[10] = gBattle_BG1_Y;
         SetGpuReg(REG_OFFSET_BLDCNT, BLDCNT_TGT2_ALL | BLDCNT_EFFECT_BLEND | BLDCNT_TGT1_BG1);
-        FillPalette(0, animBg.paletteId * 16, 32);
+        FillPalette(RGB_BLACK, animBg.paletteId * 16, 32);
         scanlineParams.dmaDest = &REG_BG1VOFS;
         var0 = WINOUT_WIN01_BG1;
         if (!IsContest())
@@ -436,7 +436,7 @@ void AnimTask_MoveAttackerMementoShadow(u8 taskId)
     {
         task->data[10] = gBattle_BG2_Y;
         SetGpuReg(REG_OFFSET_BLDCNT, BLDCNT_TGT2_ALL | BLDCNT_EFFECT_BLEND | BLDCNT_TGT1_BG2);
-        FillPalette(0, 144, 32);
+        FillPalette(RGB_BLACK, 144, 32);
         scanlineParams.dmaDest = &REG_BG2VOFS;
         var0 = WINOUT_WIN01_BG2;
         if (!IsContest())
@@ -566,12 +566,12 @@ void AnimTask_MoveTargetMementoShadow(u8 taskId)
         {
             GetBattleAnimBg1Data(&animBg);
             task->data[10] = gBattle_BG1_Y;
-            FillPalette(0, animBg.paletteId * 16, 32);
+            FillPalette(RGB_BLACK, animBg.paletteId * 16, 32);
         }
         else
         {
             task->data[10] = gBattle_BG2_Y;
-            FillPalette(0, 9 * 16, 32);
+            FillPalette(RGB_BLACK, 9 * 16, 32);
         }
 
         SetAllBattlersSpritePriority(3);
diff --git a/src/battle_script_commands.c b/src/battle_script_commands.c
index 7d1bb46a9..5f0ecad68 100644
--- a/src/battle_script_commands.c
+++ b/src/battle_script_commands.c
@@ -1037,7 +1037,7 @@ static void Cmd_jumpifaffectedbyprotect(void)
     }
 }
 
-bool8 JumpIfMoveAffectedByProtect(u16 move)
+static bool8 JumpIfMoveAffectedByProtect(u16 move)
 {
     bool8 affected = FALSE;
     if (DEFENDER_IS_PROTECTED)
diff --git a/src/berry_tag_screen.c b/src/berry_tag_screen.c
index 219454ab2..f683c73f4 100644
--- a/src/berry_tag_screen.c
+++ b/src/berry_tag_screen.c
@@ -276,7 +276,7 @@ static bool8 InitBerryTagScreen(void)
         gMain.state++;
         break;
     case 14:
-        BlendPalettes(PALETTES_ALL, 0x10, 0);
+        BlendPalettes(PALETTES_ALL, 0x10, RGB_BLACK);
         gMain.state++;
         break;
     case 15:
diff --git a/src/evolution_scene.c b/src/evolution_scene.c
index eb458d39d..085f88da5 100644
--- a/src/evolution_scene.c
+++ b/src/evolution_scene.c
@@ -212,7 +212,7 @@ void EvolutionScene(struct Pokemon* mon, u16 postEvoSpecies, bool8 canStopEvo, u
     u16 currSpecies;
     u32 trainerId, personality;
     const struct CompressedSpritePalette* pokePal;
-    u8 ID;
+    u8 id;
 
     SetHBlankCallback(NULL);
     SetVBlankCallback(NULL);
@@ -267,11 +267,11 @@ void EvolutionScene(struct Pokemon* mon, u16 postEvoSpecies, bool8 canStopEvo, u
 
     SetMultiuseSpriteTemplateToPokemon(currSpecies, B_POSITION_OPPONENT_LEFT);
     gMultiuseSpriteTemplate.affineAnims = gDummySpriteAffineAnimTable;
-    sEvoStructPtr->preEvoSpriteId = ID = CreateSprite(&gMultiuseSpriteTemplate, 120, 64, 30);
+    sEvoStructPtr->preEvoSpriteId = id = CreateSprite(&gMultiuseSpriteTemplate, 120, 64, 30);
 
-    gSprites[ID].callback = SpriteCallbackDummy_2;
-    gSprites[ID].oam.paletteNum = 1;
-    gSprites[ID].invisible = TRUE;
+    gSprites[id].callback = SpriteCallbackDummy_2;
+    gSprites[id].oam.paletteNum = 1;
+    gSprites[id].invisible = TRUE;
 
     // postEvo sprite
     DecompressPicFromTable_2(&gMonFrontPicTable[postEvoSpecies],
@@ -282,21 +282,21 @@ void EvolutionScene(struct Pokemon* mon, u16 postEvoSpecies, bool8 canStopEvo, u
 
     SetMultiuseSpriteTemplateToPokemon(postEvoSpecies, B_POSITION_OPPONENT_RIGHT);
     gMultiuseSpriteTemplate.affineAnims = gDummySpriteAffineAnimTable;
-    sEvoStructPtr->postEvoSpriteId = ID = CreateSprite(&gMultiuseSpriteTemplate, 120, 64, 30);
-    gSprites[ID].callback = SpriteCallbackDummy_2;
-    gSprites[ID].oam.paletteNum = 2;
-    gSprites[ID].invisible = TRUE;
+    sEvoStructPtr->postEvoSpriteId = id = CreateSprite(&gMultiuseSpriteTemplate, 120, 64, 30);
+    gSprites[id].callback = SpriteCallbackDummy_2;
+    gSprites[id].oam.paletteNum = 2;
+    gSprites[id].invisible = TRUE;
 
     LoadEvoSparkleSpriteAndPal();
 
-    sEvoStructPtr->evoTaskId = ID = CreateTask(Task_EvolutionScene, 0);
-    gTasks[ID].tState = 0;
-    gTasks[ID].tPreEvoSpecies = currSpecies;
-    gTasks[ID].tPostEvoSpecies = postEvoSpecies;
-    gTasks[ID].tCanStop = canStopEvo;
-    gTasks[ID].tLearnsFirstMove = TRUE;
-    gTasks[ID].tEvoWasStopped = FALSE;
-    gTasks[ID].tPartyId = partyId;
+    sEvoStructPtr->evoTaskId = id = CreateTask(Task_EvolutionScene, 0);
+    gTasks[id].tState = 0;
+    gTasks[id].tPreEvoSpecies = currSpecies;
+    gTasks[id].tPostEvoSpecies = postEvoSpecies;
+    gTasks[id].tCanStop = canStopEvo;
+    gTasks[id].tLearnsFirstMove = TRUE;
+    gTasks[id].tEvoWasStopped = FALSE;
+    gTasks[id].tPartyId = partyId;
 
     memcpy(&sEvoStructPtr->savedPalette, &gPlttBufferUnfaded[0x20], sizeof(sEvoStructPtr->savedPalette));
 
@@ -310,7 +310,7 @@ void EvolutionScene(struct Pokemon* mon, u16 postEvoSpecies, bool8 canStopEvo, u
 
 static void CB2_EvolutionSceneLoadGraphics(void)
 {
-    u8 ID;
+    u8 id;
     const struct CompressedSpritePalette* pokePal;
     u16 postEvoSpecies;
     u32 trainerId, personality;
@@ -360,10 +360,10 @@ static void CB2_EvolutionSceneLoadGraphics(void)
 
     SetMultiuseSpriteTemplateToPokemon(postEvoSpecies, B_POSITION_OPPONENT_RIGHT);
     gMultiuseSpriteTemplate.affineAnims = gDummySpriteAffineAnimTable;
-    sEvoStructPtr->postEvoSpriteId = ID = CreateSprite(&gMultiuseSpriteTemplate, 120, 64, 30);
+    sEvoStructPtr->postEvoSpriteId = id = CreateSprite(&gMultiuseSpriteTemplate, 120, 64, 30);
 
-    gSprites[ID].callback = SpriteCallbackDummy_2;
-    gSprites[ID].oam.paletteNum = 2;
+    gSprites[id].callback = SpriteCallbackDummy_2;
+    gSprites[id].oam.paletteNum = 2;
 
     SetGpuReg(REG_OFFSET_DISPCNT, DISPCNT_OBJ_ON | DISPCNT_BG_ALL_ON | DISPCNT_OBJ_1D_MAP);
 
@@ -433,14 +433,14 @@ static void CB2_TradeEvolutionSceneLoadGraphics(void)
         break;
     case 5:
         {
-            u8 ID;
+            u8 id;
 
             SetMultiuseSpriteTemplateToPokemon(postEvoSpecies, B_POSITION_OPPONENT_LEFT);
             gMultiuseSpriteTemplate.affineAnims = gDummySpriteAffineAnimTable;
-            sEvoStructPtr->postEvoSpriteId = ID = CreateSprite(&gMultiuseSpriteTemplate, 120, 64, 30);
+            sEvoStructPtr->postEvoSpriteId = id = CreateSprite(&gMultiuseSpriteTemplate, 120, 64, 30);
 
-            gSprites[ID].callback = SpriteCallbackDummy_2;
-            gSprites[ID].oam.paletteNum = 2;
+            gSprites[id].callback = SpriteCallbackDummy_2;
+            gSprites[id].oam.paletteNum = 2;
             gMain.state++;
             LinkTradeDrawWindow();
         }
@@ -451,7 +451,7 @@ static void CB2_TradeEvolutionSceneLoadGraphics(void)
             LoadWirelessStatusIndicatorSpriteGfx();
             CreateWirelessStatusIndicatorSprite(0, 0);
         }
-        BlendPalettes(PALETTES_ALL, 0x10, 0);
+        BlendPalettes(PALETTES_ALL, 0x10, RGB_BLACK);
         gMain.state++;
         break;
     case 7:
@@ -471,7 +471,7 @@ void TradeEvolutionScene(struct Pokemon* mon, u16 postEvoSpecies, u8 preEvoSprit
     u16 currSpecies;
     u32 trainerId, personality;
     const struct CompressedSpritePalette* pokePal;
-    u8 ID;
+    u8 id;
 
     GetMonData(mon, MON_DATA_NICKNAME, name);
     StringCopy_Nickname(gStringVar1, name);
@@ -496,21 +496,21 @@ void TradeEvolutionScene(struct Pokemon* mon, u16 postEvoSpecies, u8 preEvoSprit
 
     SetMultiuseSpriteTemplateToPokemon(postEvoSpecies, B_POSITION_OPPONENT_LEFT);
     gMultiuseSpriteTemplate.affineAnims = gDummySpriteAffineAnimTable;
-    sEvoStructPtr->postEvoSpriteId = ID = CreateSprite(&gMultiuseSpriteTemplate, 120, 64, 30);
+    sEvoStructPtr->postEvoSpriteId = id = CreateSprite(&gMultiuseSpriteTemplate, 120, 64, 30);
 
-    gSprites[ID].callback = SpriteCallbackDummy_2;
-    gSprites[ID].oam.paletteNum = 2;
-    gSprites[ID].invisible = TRUE;
+    gSprites[id].callback = SpriteCallbackDummy_2;
+    gSprites[id].oam.paletteNum = 2;
+    gSprites[id].invisible = TRUE;
 
     LoadEvoSparkleSpriteAndPal();
 
-    sEvoStructPtr->evoTaskId = ID = CreateTask(Task_TradeEvolutionScene, 0);
-    gTasks[ID].tState = 0;
-    gTasks[ID].tPreEvoSpecies = currSpecies;
-    gTasks[ID].tPostEvoSpecies = postEvoSpecies;
-    gTasks[ID].tLearnsFirstMove = TRUE;
-    gTasks[ID].tEvoWasStopped = FALSE;
-    gTasks[ID].tPartyId = partyId;
+    sEvoStructPtr->evoTaskId = id = CreateTask(Task_TradeEvolutionScene, 0);
+    gTasks[id].tState = 0;
+    gTasks[id].tPreEvoSpecies = currSpecies;
+    gTasks[id].tPostEvoSpecies = postEvoSpecies;
+    gTasks[id].tLearnsFirstMove = TRUE;
+    gTasks[id].tEvoWasStopped = FALSE;
+    gTasks[id].tPartyId = partyId;
 
     gBattle_BG0_X = 0;
     gBattle_BG0_Y = 0;
@@ -521,7 +521,7 @@ void TradeEvolutionScene(struct Pokemon* mon, u16 postEvoSpecies, u8 preEvoSprit
     gBattle_BG3_X = 256;
     gBattle_BG3_Y = 0;
 
-    gTextFlags.useAlternateDownArrow = 1;
+    gTextFlags.useAlternateDownArrow = TRUE;
 
     SetVBlankCallback(VBlankCB_TradeEvolutionScene);
     SetMainCallback2(CB2_TradeEvolutionSceneUpdate);
@@ -839,9 +839,9 @@ static void Task_EvolutionScene(u8 taskId)
     case EVOSTATE_CANCEL_MSG:
         if (EvoScene_IsMonAnimFinished(sEvoStructPtr->preEvoSpriteId))
         {
-            if (gTasks[taskId].tEvoWasStopped)
+            if (gTasks[taskId].tEvoWasStopped) // FRLG auto cancellation
                 StringExpandPlaceholders(gStringVar4, gText_EllipsisQuestionMark);
-            else // Fire Red leftover probably
+            else
                 StringExpandPlaceholders(gStringVar4, gText_PkmnStoppedEvolving);
 
             BattlePutTextOnWindow(gStringVar4, B_WIN_MSG);
@@ -1223,7 +1223,7 @@ static void Task_TradeEvolutionScene(u8 taskId)
         {
             DestroyTask(taskId);
             FREE_AND_SET_NULL(sEvoStructPtr);
-            gTextFlags.useAlternateDownArrow = 0;
+            gTextFlags.useAlternateDownArrow = FALSE;
             SetMainCallback2(gCB2_AfterEvolution);
         }
         break;
@@ -1644,7 +1644,7 @@ static void PauseBgPaletteAnim(void)
     if (taskId != TASK_NONE)
         gTasks[taskId].tPaused = TRUE;
 
-    FillPalette(0, 0xA0, 0x20);
+    FillPalette(RGB_BLACK, 0xA0, 0x20);
 }
 
 #undef tPaused
@@ -1658,7 +1658,7 @@ static void StopBgAnimation(void)
     if ((taskId = FindTaskIdByFunc(Task_AnimateBg)) != TASK_NONE)
         DestroyTask(taskId);
 
-    FillPalette(0, 0xA0, 0x20);
+    FillPalette(RGB_BLACK, 0xA0, 0x20);
     RestoreBgAfterAnim();
 }
 
diff --git a/src/link.c b/src/link.c
index e88cde55a..57e33c811 100644
--- a/src/link.c
+++ b/src/link.c
@@ -1595,7 +1595,7 @@ void CB2_LinkError(void)
     ResetSpriteData();
     FreeAllSpritePalettes();
     ResetPaletteFadeControl();
-    FillPalette(0, 0, 2);
+    FillPalette(RGB_BLACK, 0, 2);
     ResetTasks();
     ScanlineEffect_Stop();
     if (gWirelessCommType)
diff --git a/src/mystery_event_menu.c b/src/mystery_event_menu.c
index 702e87b3e..c35fe8ed8 100644
--- a/src/mystery_event_menu.c
+++ b/src/mystery_event_menu.c
@@ -102,7 +102,7 @@ void CB2_InitMysteryEventMenu(void)
         BuildOamBuffer();
         RunTextPrinters();
         UpdatePaletteFade();
-        FillPalette(0, 0, 2);
+        FillPalette(RGB_BLACK, 0, 2);
         SetMainCallback2(CB2_MysteryEventMenu);
     }
 }
diff --git a/src/rayquaza_scene.c b/src/rayquaza_scene.c
index 5572ef833..e3669e1f1 100644
--- a/src/rayquaza_scene.c
+++ b/src/rayquaza_scene.c
@@ -1627,7 +1627,7 @@ static void Task_DuoFightAnim(u8 taskId)
         StopMapMusic();
     }
 
-    BlendPalettes(PALETTES_ALL, 0x10, 0);
+    BlendPalettes(PALETTES_ALL, 0x10, RGB_BLACK);
     BeginNormalPaletteFade(PALETTES_ALL, 0, 0x10, 0, RGB_BLACK);
     SetVBlankCallback(VBlankCB_DuoFight);
     PlaySE(SE_DOWNPOUR);
@@ -2284,7 +2284,7 @@ static void Task_RayDescendsAnim(u8 taskId)
     LoadDescendsSceneGfx();
     SetGpuRegBits(REG_OFFSET_BLDCNT, BLDCNT_TGT1_BG0 | BLDCNT_TGT2_BG1 | BLDCNT_TGT2_BG2 | BLDCNT_TGT2_BG3 | BLDCNT_TGT2_OBJ | BLDCNT_EFFECT_BLEND);
     SetGpuReg(REG_OFFSET_BLDALPHA, BLDALPHA_BLEND(0, 16));
-    BlendPalettes(PALETTES_ALL, 0x10, 0);
+    BlendPalettes(PALETTES_ALL, 0x10, RGB_BLACK);
     SetVBlankCallback(VBlankCB_RayquazaScene);
     sRayScene->revealedLightLine = 0;
     sRayScene->revealedLightTimer = 0;
@@ -2501,7 +2501,7 @@ static void Task_RayChargesAnim(u8 taskId)
     InitChargesSceneBgs();
     LoadChargesSceneGfx();
     SetWindowsHideVertBorders();
-    BlendPalettes(PALETTES_ALL, 0x10, 0);
+    BlendPalettes(PALETTES_ALL, 0x10, RGB_BLACK);
     SetVBlankCallback(VBlankCB_RayquazaScene);
     tState = 0;
     tTimer = 0;
@@ -2697,7 +2697,7 @@ static void Task_RayChasesAwayAnim(u8 taskId)
     ClearGpuRegBits(REG_OFFSET_DISPCNT, DISPCNT_BG2_ON);
     SetGpuReg(REG_OFFSET_BLDCNT, BLDCNT_TGT1_BG0 | BLDCNT_TGT2_BG1 | BLDCNT_EFFECT_BLEND);
     SetGpuReg(REG_OFFSET_BLDALPHA, BLDALPHA_BLEND(9, 14));
-    BlendPalettes(PALETTES_ALL, 0x10, 0);
+    BlendPalettes(PALETTES_ALL, 0x10, RGB_BLACK);
     SetVBlankCallback(VBlankCB_RayquazaScene);
     tState = 0;
     tTimer = 0;