Pokemon X' & 'Y': Starter Pokemon Evolutions Revealed

Game Freak has finally unveiled the secondary stages for the starter Pokemon in
Game Freak has finally unveiled the secondary stages for the starter Pokemon in 'Pokemon X' and 'Y', along with a new trailer showing the beasts in action.

New Pokemon - Pokemon X and Y Guide - IGN

Pokémon X Preview - New Pokémon X & Y Trailer Reveals Trainer Customization, New Mewtwo Mega Evolution - Game Informer

Pokémon Sword and Shield starter evolutions may have leaked - Polygon

JEFusion Japanese Entertainment Blog - The Center of Tokusatsu: Mewtwo Gets Another Mega, Starter Evolutions in Pokémon XY Revealed

Pokémon X and Y - Kalos Starter Evolutions Revealed

Pokémon XY Leaks, Page 68

Black & White starter evolutions revealed

Pokemon X and Y Starter Final Evolutions Revealed - The PokeMasters

RUMOR: Final Starter Evolutions Leaked?

Pokémon on X: Froakie's final evolved form has been revealed! Meet Greninja! #PokemonXY / X