diff --git a/Data/Scripts/012_Battle/001_Battler/002_Battler_Initialize.rb b/Data/Scripts/012_Battle/001_Battler/002_Battler_Initialize.rb
index 2924f693d..fcdfd3aa4 100644
--- a/Data/Scripts/012_Battle/001_Battler/002_Battler_Initialize.rb
+++ b/Data/Scripts/012_Battle/001_Battler/002_Battler_Initialize.rb
@@ -195,7 +195,7 @@ class PokeBattle_Battler
     @effects[PBEffects::Illusion]            = nil
     if hasActiveAbility?(:ILLUSION)
       idxLastParty = @battle.pbLastInTeam(@index)
-      if idxLastParty!=@pokemonIndex
+      if idxLastParty >= 0 && idxLastParty != @pokemonIndex
         @effects[PBEffects::Illusion]        = @battle.pbParty(@index)[idxLastParty]
       end
     end
diff --git a/Data/Scripts/012_Battle/002_Move/005_Move_Effects_000-07F.rb b/Data/Scripts/012_Battle/002_Move/005_Move_Effects_000-07F.rb
index e6851ef05..c814aa0b7 100644
--- a/Data/Scripts/012_Battle/002_Move/005_Move_Effects_000-07F.rb
+++ b/Data/Scripts/012_Battle/002_Move/005_Move_Effects_000-07F.rb
@@ -273,7 +273,7 @@ end
 #===============================================================================
 class PokeBattle_Move_012 < PokeBattle_FlinchMove
   def pbMoveFailed?(user,targets)
-    if user.turnCount>1 || user.lastRoundMoved>=0
+    if user.turnCount > 1
       @battle.pbDisplay(_INTL("But it failed!"))
       return true
     end
diff --git a/Data/Scripts/012_Battle/002_Move/007_Move_Effects_100-17F.rb b/Data/Scripts/012_Battle/002_Move/007_Move_Effects_100-17F.rb
index d66a2b0fc..cf5269018 100644
--- a/Data/Scripts/012_Battle/002_Move/007_Move_Effects_100-17F.rb
+++ b/Data/Scripts/012_Battle/002_Move/007_Move_Effects_100-17F.rb
@@ -1556,7 +1556,7 @@ end
 #===============================================================================
 class PokeBattle_Move_149 < PokeBattle_Move
   def pbMoveFailed?(user,targets)
-    if user.turnCount>1 || user.lastRoundMoved>=0
+    if user.turnCount > 1
       @battle.pbDisplay(_INTL("But it failed!"))
       return true
     end
@@ -2575,7 +2575,7 @@ end
 #===============================================================================
 class PokeBattle_Move_174 < PokeBattle_Move
   def pbMoveFailed?(user,targets)
-    if user.turnCount>1 || user.lastRoundMoved>=0
+    if user.turnCount > 1
       @battle.pbDisplay(_INTL("But it failed!"))
       return true
     end
diff --git a/Data/Scripts/012_Battle/003_Battle/006_Battle_Action_Switching.rb b/Data/Scripts/012_Battle/003_Battle/006_Battle_Action_Switching.rb
index f7124396b..f361a0cb5 100644
--- a/Data/Scripts/012_Battle/003_Battle/006_Battle_Action_Switching.rb
+++ b/Data/Scripts/012_Battle/003_Battle/006_Battle_Action_Switching.rb
@@ -169,7 +169,8 @@ class PokeBattle_Battle
             idxPartyForName = idxPartyNew
             enemyParty = pbParty(idxBattler)
             if enemyParty[idxPartyNew].ability == :ILLUSION
-              idxPartyForName = pbLastInTeam(idxBattler)
+              new_index = pbLastInTeam(idxBattler)
+              idxPartyForName = new_index if new_index >= 0
             end
             if pbDisplayConfirm(_INTL("{1} is about to send in {2}. Will you switch your Pokémon?",
                opponent.full_name, enemyParty[idxPartyForName].name))
@@ -255,7 +256,8 @@ class PokeBattle_Battle
     party = pbParty(idxBattler)
     newPkmnName = party[idxParty].name
     if party[idxParty].ability == :ILLUSION
-      newPkmnName = party[pbLastInTeam(idxBattler)].name
+      new_index = pbLastInTeam(idxBattler)
+      newPkmnName = party[new_index].name if new_index >= 0
     end
     if pbOwnedByPlayer?(idxBattler)
       opposing = @battlers[idxBattler].pbDirectOpposing
diff --git a/Data/Scripts/012_Battle/004_AI/005_AI_Move_EffectScores.rb b/Data/Scripts/012_Battle/004_AI/005_AI_Move_EffectScores.rb
index e3f2b99d2..23bef89e3 100644
--- a/Data/Scripts/012_Battle/004_AI/005_AI_Move_EffectScores.rb
+++ b/Data/Scripts/012_Battle/004_AI/005_AI_Move_EffectScores.rb
@@ -3026,7 +3026,7 @@ class PokeBattle_AI
     when "173"
     #---------------------------------------------------------------------------
     when "174"
-      score -= 90 if user.turnCount>0 || user.lastRoundMoved>=0
+      score -= 90 if user.turnCount > 0
     #---------------------------------------------------------------------------
     when "175"
       score += 30 if target.effects[PBEffects::Minimize]
diff --git a/Data/Scripts/012_Battle/007_BattleHandlers_Abilities.rb b/Data/Scripts/012_Battle/007_BattleHandlers_Abilities.rb
index 95e282903..6fa166bce 100644
--- a/Data/Scripts/012_Battle/007_BattleHandlers_Abilities.rb
+++ b/Data/Scripts/012_Battle/007_BattleHandlers_Abilities.rb
@@ -1661,7 +1661,7 @@ BattleHandlers::UserAbilityEndOfMove.add(:BEASTBOOST,
 
 BattleHandlers::UserAbilityEndOfMove.add(:MAGICIAN,
   proc { |ability,user,targets,move,battle|
-    next if !battle.futureSight
+    next if battle.futureSight
     next if !move.pbDamagingMove?
     next if user.item
     next if battle.wildBattle? && user.opposes?