Kickback in the art picture.
Kickback is one of the most charming, likable beings you're ever likely to meet. He collects friends the way others do energon cubes. Scratch the surface, though, and you find a manipulative blackmailer that loves digging up dirt on his new "pals" to force them to work for him. Humans are particularly likely to fall prey to his honeyed words. In insect mode his super-charged legs allow him to jump great distances and kick through solid steel, though he's vulnerable in that mode when attempting to fly through high winds.
His alt-mode is a Grasshopper.
Gallery
Kickback in Grasshopper Mode.