Added Gen 9 forms code, evolution code, some item effects

Data/Scripts/014_Pokemon/001_Pokemon.rb

@@ -252,8 +252,10 @@ class Pokemon
   # @param value [Integer] new HP value
   def hp=(value)
     @hp = value.clamp(0, @totalhp)
-    heal_status if @hp == 0
-    @ready_to_evolve = false if @hp == 0
+    return if @hp > 0
+    heal_status
+    @ready_to_evolve = false
+    @evolution_counter = 0 if isSpecies?(:BASCULIN) || isSpecies?(:YAMASK)
   end
 
   # Sets this Pokémon's status. See {GameData::Status} for all possible status effects.
@@ -988,6 +990,16 @@ class Pokemon
     end
   end
 
+  # Checks whether this Pokemon can evolve because of levelling up in battle.
+  # This also checks call_level_up as above.
+  # @return [Symbol, nil] the ID of the species to evolve into
+  def check_evolution_on_battle_level_up
+    return check_evolution_internal do |pkmn, new_species, method, parameter|
+      success = GameData::Evolution.get(method).call_battle_level_up(pkmn, parameter)
+      next (success) ? new_species : nil
+    end
+  end
+
   # Checks whether this Pokemon can evolve because of using an item on it.
   # @param item_used [Symbol, GameData::Item, nil] the item being used
   # @return [Symbol, nil] the ID of the species to evolve into