Made more use of nil_or_empty?, fixed incorrect default species body shape, fixed Illusion, fixed potential foreign Pokémon with blank names

Data/Scripts/011_Battle/001_Battler/001_PokeBattle_Battler.rb

@@ -344,7 +344,7 @@ class PokeBattle_Battler
   def hasActiveAbility?(check_ability, ignore_fainted = false)
     return false if !abilityActive?(ignore_fainted)
     return check_ability.include?(@ability_id) if check_ability.is_a?(Array)
-    return check_ability == self.ability
+    return self.ability == check_ability
   end
   alias hasWorkingAbility hasActiveAbility?
 

Data/Scripts/011_Battle/001_Battler/003_Battler_ChangeSelf.rb

@@ -37,7 +37,7 @@ class PokeBattle_Battler
       @battle.pbHideAbilitySplash(target)
       pbItemHPHealCheck
     else
-      msg = _INTL("{1} had its energy drained!",target.pbThis) if !msg || msg==""
+      msg = _INTL("{1} had its energy drained!",target.pbThis) if nil_or_empty?(msg)
       @battle.pbDisplay(msg)
       if canHeal?
         amt = (amt*1.3).floor if hasActiveItem?(:BIGROOT)

Data/Scripts/011_Battle/001_Battler/004_Battler_Statuses.rb

@@ -484,7 +484,7 @@ class PokeBattle_Battler
   def pbConfuse(msg=nil)
     @effects[PBEffects::Confusion] = pbConfusionDuration
     @battle.pbCommonAnimation("Confusion",self)
-    msg = _INTL("{1} became confused!",pbThis) if !msg || msg==""
+    msg = _INTL("{1} became confused!",pbThis) if nil_or_empty?(msg)
     @battle.pbDisplay(msg)
     PBDebug.log("[Lingering effect] #{pbThis}'s confusion count is #{@effects[PBEffects::Confusion]}")
     # Confusion cures
@@ -551,7 +551,7 @@ class PokeBattle_Battler
   def pbAttract(user,msg=nil)
     @effects[PBEffects::Attract] = user.index
     @battle.pbCommonAnimation("Attract",self)
-    msg = _INTL("{1} fell in love!",pbThis) if !msg || msg==""
+    msg = _INTL("{1} fell in love!",pbThis) if nil_or_empty?(msg)
     @battle.pbDisplay(msg)
     # Destiny Knot
     if hasActiveItem?(:DESTINYKNOT) && user.pbCanAttract?(self,false)

Data/Scripts/011_Battle/003_Battle/002_PokeBattle_Battle.rb

@@ -401,7 +401,7 @@ class PokeBattle_Battle
     party.each_with_index do |pkmn,i|
       next if i<idxPartyStart || i>=idxPartyEnd   # Check the team only
       next if !pkmn || !pkmn.able?   # Can't copy a non-fainted Pokémon or egg
-      ret = i if partyOrders[i]>partyOrders[ret]
+      ret = i if ret < 0 || partyOrders[i] > partyOrders[ret]
     end
     return ret
   end

Data/Scripts/011_Battle/003_Battle/006_Battle_Action_Switching.rb

@@ -170,7 +170,7 @@ class PokeBattle_Battle
             enemyParty = pbParty(idxBattler)
             if enemyParty[idxPartyNew].ability == :ILLUSION
               new_index = pbLastInTeam(idxBattler)
-              idxPartyForName = new_index if new_index >= 0
+              idxPartyForName = new_index if new_index >= 0 && new_index != idxPartyNew
             end
             if pbDisplayConfirm(_INTL("{1} is about to send in {2}. Will you switch your Pokémon?",
                opponent.full_name, enemyParty[idxPartyForName].name))
@@ -257,7 +257,7 @@ class PokeBattle_Battle
     newPkmnName = party[idxParty].name
     if party[idxParty].ability == :ILLUSION
       new_index = pbLastInTeam(idxBattler)
-      newPkmnName = party[new_index].name if new_index >= 0
+      newPkmnName = party[new_index].name if new_index >= 0 && new_index != idxParty
     end
     if pbOwnedByPlayer?(idxBattler)
       opposing = @battlers[idxBattler].pbDirectOpposing

Data/Scripts/011_Battle/003_Battle/009_Battle_Action_Other.rb

@@ -147,9 +147,7 @@ class PokeBattle_Battle
     @scene.pbRefreshOne(idxBattler)
     pbCommonAnimation("MegaEvolution2",battler)
     megaName = battler.pokemon.megaName
-    if !megaName || megaName==""
-      megaName = _INTL("Mega {1}", battler.pokemon.speciesName)
-    end
+    megaName = _INTL("Mega {1}", battler.pokemon.speciesName) nil_or_empty?(megaName)
     pbDisplay(_INTL("{1} has Mega Evolved into {2}!",battler.pbThis,megaName))
     side  = battler.idxOwnSide
     owner = pbGetOwnerIndexFromBattlerIndex(idxBattler)

Data/Scripts/011_Battle/005_Battle scene/005_PokeBattle_SceneMenus.rb

@@ -538,7 +538,7 @@ class TargetMenuDisplay < BattleMenuBase
     @overlay.bitmap.clear
     textpos = []
     @buttons.each_with_index do |button,i|
-      next if !button || @texts[i].nil? || @texts[i]==""
+      next if !button || nil_or_empty?(@texts[i])
       x = button.x-self.x+button.src_rect.width/2
       y = button.y-self.y+2
       textpos.push([@texts[i],x,y,2,TEXT_BASE_COLOR,TEXT_SHADOW_COLOR])

Data/Scripts/011_Battle/005_Battle scene/009_Scene_Animations.rb

@@ -480,7 +480,7 @@ class PokeBattle_Scene
 
   # Plays a common animation.
   def pbCommonAnimation(animName,user=nil,target=nil)
-    return if !animName || animName==""
+    return if nil_or_empty?(animName)
     target = target[0] if target && target.is_a?(Array)
     animations = pbLoadBattleAnimations
     return if !animations