Probably Plastic Man. He'll start off far more powerful than Buddy, and has enough immunities that it should take some time before Buddy can find something to put him down.
ASB
AsbestosFlaygonThe Original One
Or Plastic Man slips through AM's insides and expands himself.
OS
Original Smurphtu quoqumber
Originally posted by AsbestosFlaygon Or Plastic Man slips through AM's insides and expands himself.
... or just suffocates him, beats the pulp out of him, chops him into pieces, etc.