Supergirl was infected with the evil mentalities of Mata Hari, Lady Macbeth, and Lucrezia Borgia through Ravenne's hypno-dominator, and, against her will, was forced to steal, concoct a Kryptonite-based poison, and then feed the poison to Comet, who collapsed, to a released Phantom Zone prisoner, Py-Ron, and then to Superman, both of whom apparently died - and then, to herself. But, unknown to them, Comet was not affected by the poison, not being Kryptonian, and secretly altered the brew with his super-vision to make it produce a non-fatal reaction.
Py-Ron, who recovered first, donned a Superman-like uniform he once used in a short career as 'Evil-Man' and, by pushing Feminax off its axis, caused global disasters that killed all the Sisterhood of Evil and everyone else on the planet. Superman and Supergirl judged Py-Ron guilty of mass murder, despite the fact that he intended to punish evildoers, and banished him to the Phantom Zone again.
