Kyle Rayner
During his banishment to Earth, Grayven is infected with a variant of Joker toxin that causes insanity. He attempts to perform at, and then destroy, a comedy club. Kyle Rayner again stops him. Grayven later reappeared in "Ion: Guardian of the Universe". There he is revealed to have sent Nero and Effigy after Kyle Rayner. Grayven also is implied to be part of some larger conspiracy, most likely that of the Sinestro Corps due to his hunting of escaped Qwardians and knowledge of Kyle's sick mother. Rayner blasts Grayven into unconsciousness.