Pokémon X and Pokémon Y

Probably not given anime mewtwo changes between forms at will in the ova/film.

It's probably a hold item or you can change it between forms at a certain place.

edit: Serebii says it's a hold item.

- Pokémon can only Mega Evolve when they are holding a Mega Stone
- Blazikenite is not found within normal gameplay
- Mega Evolutions are temporary in battle
- not all Pokémon will have Mega Evolutions
- the Master Tower has a connection to Mega Evolutions
- stat increases confimed, with MegaLucario's Attack being higher
- MegaAbsol has increased Attack & Speed
- Super Training will increase Pokémon's "Kiso" Points
- next CoroCoro will feature new Pokémon, new Mega Evolutions and a type chart featuring the Fairy-type

I wonder how common Mega's will be in tournament teams. On top of that will they be banned like how most legendaries are? Additionally will we get more Mega's in the next generation or is this a gen 6 only thing?