Mega Evolution (Japanese: メガ進化 Mega Shinka) is the second evolution method introduced in Pokemon X and Y and consists in certain Pokémon gaining an ultimate form of themselves. Thought to be transformation method, Professor Kaless knowledges that Mega Evolution was second evolution method which is allows to evolve and devolve after the battle. The Pokémon need special Mega Stones in order to evolve into their Mega Evolution forms, the final forms for one-evolution families and ultimate (second/true final) forms for two-evolution families.