Temperament

Once during your turn (before your attack), you may search your deck for any Castform and switch it with Castform Sunny Form. (Any cards attached to Castform Sunny Form, damage counters, Special Conditions, and effects on it are now on the new Pokémon.) Shuffle Castform Sunny Form back into your deck. You can't use more than 1 Temperament Poké-Power each turn.

Ember

Discard a Fire Energy attached to Castform Sunny Form.

Its appearance changes with the weather. Recently, its molecules were found to be just like water.