diff --git a/Data/Scripts/015_Items/002_PItem_ItemEffects.rb b/Data/Scripts/015_Items/002_PItem_ItemEffects.rb
index 6f544747c..b40202189 100644
--- a/Data/Scripts/015_Items/002_PItem_ItemEffects.rb
+++ b/Data/Scripts/015_Items/002_PItem_ItemEffects.rb
@@ -837,7 +837,7 @@ ItemHandlers::UseOnPokemon.add(:TAMATOBERRY,proc { |item,pkmn,scene|
 })
 
 ItemHandlers::UseOnPokemon.add(:GRACIDEA,proc { |item,pkmn,scene|
-  if !isConst?(pkmn.species,PBSpecies,:SHAYMIN) || pkmn.form!=0 ||
+  if !pkmn.isSpecies?(:SHAYMIN) || pkmn.form!=0 ||
      pkmn.status==PBStatuses::FROZEN || PBDayNight.isNight?
     scene.pbDisplay(_INTL("It had no effect."))
     next false
@@ -854,7 +854,7 @@ ItemHandlers::UseOnPokemon.add(:GRACIDEA,proc { |item,pkmn,scene|
 })
 
 ItemHandlers::UseOnPokemon.add(:REDNECTAR,proc { |item,pkmn,scene|
-  if !isConst?(pkmn.species,PBSpecies,:ORICORIO) || pkmn.form==0
+  if !pkmn.isSpecies?(:ORICORIO) || pkmn.form==0
     scene.pbDisplay(_INTL("It had no effect."))
     next false
   end
@@ -869,7 +869,7 @@ ItemHandlers::UseOnPokemon.add(:REDNECTAR,proc { |item,pkmn,scene|
 })
 
 ItemHandlers::UseOnPokemon.add(:YELLOWNECTAR,proc { |item,pkmn,scene|
-  if !isConst?(pkmn.species,PBSpecies,:ORICORIO) || pkmn.form==1
+  if !pkmn.isSpecies?(:ORICORIO) || pkmn.form==1
     scene.pbDisplay(_INTL("It had no effect."))
     next false
   end
@@ -884,7 +884,7 @@ ItemHandlers::UseOnPokemon.add(:YELLOWNECTAR,proc { |item,pkmn,scene|
 })
 
 ItemHandlers::UseOnPokemon.add(:PINKNECTAR,proc { |item,pkmn,scene|
-  if !isConst?(pkmn.species,PBSpecies,:ORICORIO) || pkmn.form==2
+  if !pkmn.isSpecies?(:ORICORIO) || pkmn.form==2
     scene.pbDisplay(_INTL("It had no effect."))
     next false
   end
@@ -899,7 +899,7 @@ ItemHandlers::UseOnPokemon.add(:PINKNECTAR,proc { |item,pkmn,scene|
 })
 
 ItemHandlers::UseOnPokemon.add(:PURPLENECTAR,proc { |item,pkmn,scene|
-  if !isConst?(pkmn.species,PBSpecies,:ORICORIO) || pkmn.form==3
+  if !pkmn.isSpecies?(:ORICORIO) || pkmn.form==3
     scene.pbDisplay(_INTL("It had no effect."))
     next false
   end
@@ -914,9 +914,9 @@ ItemHandlers::UseOnPokemon.add(:PURPLENECTAR,proc { |item,pkmn,scene|
 })
 
 ItemHandlers::UseOnPokemon.add(:REVEALGLASS,proc { |item,pkmn,scene|
-  if !isConst?(pkmn.species,PBSpecies,:TORNADUS) &&
-     !isConst?(pkmn.species,PBSpecies,:THUNDURUS) &&
-     !isConst?(pkmn.species,PBSpecies,:LANDORUS)
+  if !pkmn.isSpecies?(:TORNADUS) &&
+     !pkmn.isSpecies?(:THUNDURUS) &&
+     !pkmn.isSpecies?(:LANDORUS)
     scene.pbDisplay(_INTL("It had no effect."))
     next false
   end
@@ -933,7 +933,7 @@ ItemHandlers::UseOnPokemon.add(:REVEALGLASS,proc { |item,pkmn,scene|
 })
 
 ItemHandlers::UseOnPokemon.add(:PRISONBOTTLE,proc { |item,pkmn,scene|
-  if !isConst?(pkmn.species,PBSpecies,:HOOPA)
+  if !pkmn.isSpecies?(:HOOPA)
     scene.pbDisplay(_INTL("It had no effect."))
     next false
   end
@@ -949,7 +949,7 @@ ItemHandlers::UseOnPokemon.add(:PRISONBOTTLE,proc { |item,pkmn,scene|
 })
 
 ItemHandlers::UseOnPokemon.add(:DNASPLICERS,proc { |item,pkmn,scene|
-  if !isConst?(pkmn.species,PBSpecies,:KYUREM)
+  if !pkmn.isSpecies?(:KYUREM)
     scene.pbDisplay(_INTL("It had no effect."))
     next false
   end
@@ -967,13 +967,13 @@ ItemHandlers::UseOnPokemon.add(:DNASPLICERS,proc { |item,pkmn,scene|
       scene.pbDisplay(_INTL("It cannot be fused with an Egg."))
     elsif poke2.fainted?
       scene.pbDisplay(_INTL("It cannot be fused with that fainted Pokémon."))
-    elsif !isConst?(poke2.species,PBSpecies,:RESHIRAM) &&
-          !isConst?(poke2.species,PBSpecies,:ZEKROM)
+    elsif !poke2.isSpecies?(:RESHIRAM) &&
+          !poke2.isSpecies?(:ZEKROM)
       scene.pbDisplay(_INTL("It cannot be fused with that Pokémon."))
     end
     newForm = 0
-    newForm = 1 if isConst?(poke2.species,PBSpecies,:RESHIRAM)
-    newForm = 2 if isConst?(poke2.species,PBSpecies,:ZEKROM)
+    newForm = 1 if poke2.isSpecies?(:RESHIRAM)
+    newForm = 2 if poke2.isSpecies?(:ZEKROM)
     pkmn.setForm(newForm) {
       pkmn.fused = poke2
       pbRemovePokemonAt(chosen)
@@ -997,7 +997,7 @@ ItemHandlers::UseOnPokemon.add(:DNASPLICERS,proc { |item,pkmn,scene|
 })
 
 ItemHandlers::UseOnPokemon.add(:NSOLARIZER,proc { |item,pkmn,scene|
-  if !isConst?(pkmn.species,PBSpecies,:NECROZMA) || pkmn.form==0
+  if !pkmn.isSpecies?(:NECROZMA) || pkmn.form==0
     scene.pbDisplay(_INTL("It had no effect."))
     next false
   end
@@ -1015,7 +1015,7 @@ ItemHandlers::UseOnPokemon.add(:NSOLARIZER,proc { |item,pkmn,scene|
       scene.pbDisplay(_INTL("It cannot be fused with an Egg."))
     elsif poke2.fainted?
       scene.pbDisplay(_INTL("It cannot be fused with that fainted Pokémon."))
-    elsif !isConst?(poke2.species,PBSpecies,:SOLGALEO)
+    elsif !poke2.isSpecies?(:SOLGALEO)
       scene.pbDisplay(_INTL("It cannot be fused with that Pokémon."))
     end
     pkmn.setForm(1) {
@@ -1041,7 +1041,7 @@ ItemHandlers::UseOnPokemon.add(:NSOLARIZER,proc { |item,pkmn,scene|
 })
 
 ItemHandlers::UseOnPokemon.add(:NLUNARIZER,proc { |item,pkmn,scene|
-  if !isConst?(pkmn.species,PBSpecies,:NECROZMA) || pkmn.form==1
+  if !pkmn.isSpecies?(:NECROZMA) || pkmn.form==1
     scene.pbDisplay(_INTL("It had no effect."))
     next false
   end
@@ -1059,7 +1059,7 @@ ItemHandlers::UseOnPokemon.add(:NLUNARIZER,proc { |item,pkmn,scene|
       scene.pbDisplay(_INTL("It cannot be fused with an Egg."))
     elsif poke2.fainted?
       scene.pbDisplay(_INTL("It cannot be fused with that fainted Pokémon."))
-    elsif !isConst?(poke2.species,PBSpecies,:LUNALA)
+    elsif !poke2.isSpecies?(:LUNALA)
       scene.pbDisplay(_INTL("It cannot be fused with that Pokémon."))
     end
     pkmn.setForm(2) {
@@ -1091,8 +1091,7 @@ ItemHandlers::UseOnPokemon.add(:ABILITYCAPSULE,proc { |item,pkmn,scene|
     abil1 = i[0] if i[1]==0
     abil2 = i[0] if i[1]==1
   end
-  if abil1<=0 || abil2<=0 || pkmn.hasHiddenAbility? ||
-     isConst?(pkmn.species,PBSpecies,:ZYGARDE)
+  if abil1<=0 || abil2<=0 || pkmn.hasHiddenAbility? || pkmn.isSpecies?(:ZYGARDE)
     scene.pbDisplay(_INTL("It won't have any effect."))
     next false
   end
diff --git a/Data/Scripts/016_Pokemon/004_Pokemon_ShadowPokemon.rb b/Data/Scripts/016_Pokemon/004_Pokemon_ShadowPokemon.rb
index 1865f72c2..9d178a5f2 100644
--- a/Data/Scripts/016_Pokemon/004_Pokemon_ShadowPokemon.rb
+++ b/Data/Scripts/016_Pokemon/004_Pokemon_ShadowPokemon.rb
@@ -193,7 +193,7 @@ end
 #===============================================================================
 def pbIsPurifiable?(pkmn)
   return false if !pkmn
-  return false if isConst?(pkmn.species,PBSpecies,:LUGIA)
+  return false if pkmn.isSpecies?(:LUGIA)
   return false if !pkmn.shadowPokemon? || pkmn.heartgauge>0
   return true
 end
diff --git a/Data/Scripts/016_Pokemon/008_Pokemon_Storage.rb b/Data/Scripts/016_Pokemon/008_Pokemon_Storage.rb
index 2d6f286f1..8a4b0a037 100644
--- a/Data/Scripts/016_Pokemon/008_Pokemon_Storage.rb
+++ b/Data/Scripts/016_Pokemon/008_Pokemon_Storage.rb
@@ -181,7 +181,7 @@ class PokemonStorage
       pkmn = self[boxSrc,indexSrc]
       raise "Trying to copy nil to storage" if !pkmn
       pkmn.formTime = nil if pkmn.respond_to?("formTime")
-      pkmn.form     = 0 if isConst?(pkmn.species,PBSpecies,:SHAYMIN)
+      pkmn.form     = 0 if pkmn.isSpecies?(:SHAYMIN)
       pkmn.heal
       self[boxDst,indexDst] = pkmn
     end
@@ -204,7 +204,7 @@ class PokemonStorage
       if self[box,i]==nil
         if box>=0
           pkmn.formTime = nil if pkmn.respond_to?("formTime") && pkmn.formTime
-          pkmn.form     = 0 if isConst?(pkmn.species,PBSpecies,:SHAYMIN)
+          pkmn.form     = 0 if pkmn.isSpecies?(:SHAYMIN)
           pkmn.heal
         end
         self[box,i] = pkmn
@@ -217,7 +217,7 @@ class PokemonStorage
   def pbStoreCaught(pkmn)
     if @currentBox>=0
       pkmn.formTime = nil if pkmn.respond_to?("formTime")
-      pkmn.form     = 0 if isConst?(pkmn.species,PBSpecies,:SHAYMIN)
+      pkmn.form     = 0 if pkmn.isSpecies?(:SHAYMIN)
       pkmn.heal
     end
     for i in 0...maxPokemon(@currentBox)
diff --git a/Data/Scripts/017_UI/017_PScreen_PokemonStorage.rb b/Data/Scripts/017_UI/017_PScreen_PokemonStorage.rb
index 387fc23f5..62cca7d32 100644
--- a/Data/Scripts/017_UI/017_PScreen_PokemonStorage.rb
+++ b/Data/Scripts/017_UI/017_PScreen_PokemonStorage.rb
@@ -1760,7 +1760,7 @@ class PokemonStorageScreen
     end
     if box>=0
       @heldpkmn.formTime = nil if @heldpkmn.respond_to?("formTime")
-      @heldpkmn.form     = 0 if isConst?(@heldpkmn.species,PBSpecies,:SHAYMIN)
+      @heldpkmn.form     = 0 if @heldpkmn.isSpecies?(:SHAYMIN)
       @heldpkmn.heal
     end
     @scene.pbPlace(selected,@heldpkmn)
@@ -1789,7 +1789,7 @@ class PokemonStorageScreen
     end
     if box>=0
       @heldpkmn.formTime = nil if @heldpkmn.respond_to?("formTime")
-      @heldpkmn.form     = 0 if isConst?(@heldpkmn.species,PBSpecies,:SHAYMIN)
+      @heldpkmn.form     = 0 if @heldpkmn.isSpecies?(:SHAYMIN)
       @heldpkmn.heal
     end
     @scene.pbSwap(selected,@heldpkmn)
diff --git a/Data/Scripts/019_Other battles/004_PBattle_OrgBattleRules.rb b/Data/Scripts/019_Other battles/004_PBattle_OrgBattleRules.rb
index 4fd018f63..e6a55192b 100644
--- a/Data/Scripts/019_Other battles/004_PBattle_OrgBattleRules.rb	
+++ b/Data/Scripts/019_Other battles/004_PBattle_OrgBattleRules.rb	
@@ -405,12 +405,12 @@ class StandardRestriction
     # Certain named species are not banned
     speciesWhitelist = [:DRAGONITE,:SALAMENCE,:TYRANITAR]
     for i in speciesWhitelist
-      return true if isConst?(pokemon.species,PBSpecies,i)
+      return true if pokemon.isSpecies?(i)
     end
     # Certain named species are banned
     speciesBlacklist = [:WYNAUT,:WOBBUFFET]
     for i in speciesBlacklist
-      return false if isConst?(pokemon.species,PBSpecies,i)
+      return false if pokemon.isSpecies?(i)
     end
     # Species with total base stat 600 or more are banned
     baseStats = pbGetSpeciesData(pokemon.species,pokemon.form,SpeciesBaseStats)
@@ -498,7 +498,7 @@ end
 
 class NegativeExtendedGameClause
   def isValid?(pokemon)
-    return false if isConst?(pokemon.species,PBSpecies,:ARCEUS)
+    return false if pokemon.isSpecies?(:ARCEUS)
     return false if isConst?(pokemon.item,PBItems,:MICLEBERRY)
     return false if isConst?(pokemon.item,PBItems,:CUSTAPBERRY)
     return false if isConst?(pokemon.item,PBItems,:JABOCABERRY)
@@ -605,12 +605,12 @@ class LittleCupRestriction
     return false if isConst?(pokemon.item,PBItems,:DEEPSEATOOTH)
     return false if pokemon.hasMove?(:SONICBOOM)
     return false if pokemon.hasMove?(:DRAGONRAGE)
-    return false if isConst?(pokemon.species,PBSpecies,:SCYTHER)
-    return false if isConst?(pokemon.species,PBSpecies,:SNEASEL)
-    return false if isConst?(pokemon.species,PBSpecies,:MEDITITE)
-    return false if isConst?(pokemon.species,PBSpecies,:YANMA)
-    return false if isConst?(pokemon.species,PBSpecies,:TANGELA)
-    return false if isConst?(pokemon.species,PBSpecies,:MURKROW)
+    return false if pokemon.isSpecies?(:SCYTHER)
+    return false if pokemon.isSpecies?(:SNEASEL)
+    return false if pokemon.isSpecies?(:MEDITITE)
+    return false if pokemon.isSpecies?(:YANMA)
+    return false if pokemon.isSpecies?(:TANGELA)
+    return false if pokemon.isSpecies?(:MURKROW)
     return true
   end
 end