Pokemon were known for evolving into bigger and stronger Pokemon ever since the first game. Before they would evolve by leveling up or with some type of stone and it would be permanent but in Pokemon X and Y there's a new stone that you will get in which will allow certain Pokemon to MEGA evolve during battle in which it only last for that battle then you return back to your normal self. Pokemon X and Y is just around the corner being released on October 12, 2013 and they shown off quite a few Mega Evolutions and here they are!

Pokemon were known for evolving into bigger and stronger Pokemon ever since the first game. Before they would evolve by leveling up or with some type of stone and it would be permanent but in Pokemon X and Y there's a new stone that you will get in which will allow certain Pokemon to MEGA evolve during battle in which it only last for that battle then you return back to your normal self.