This One Goes to 11 Ben 10 : Season 3 Episode 2

During one last stop by a toy store before Ben, Gwen, and Grandpa Max's maiden voyage across the Atlantic, Ben runs into an old bully, Kevin 11, who now has new powers. He's able to transform into aliens just like Ben, such as the "bootleg" doppelgänger of Cannonbolt— Wreckingbolt!