10 Times Supervillains Killed Other Villains
8. Catwoman Kills Black Mask - Catwoman, Vol. 3
Catwoman is another character who left behind the mantle of 'supervillain' years ago, becoming a staunch ally of the Bat Family along the way, but there's no escaping the fact she was once a key member of Batman's rogues gallery too.
And despite Selina Kyle adopting the less-than-lethal methods of Gotham's vigilantes, she's definitely less reluctant to cross the line the Dark Knight and his allies daren't touch. One of the most famous instances of Catwoman crossing that line came in the third volume of the character's series, where her rivalry with Black Mask, aka Roman Sionis, was rekindled.
Sionis and Kyle had crossed paths before, with the former attempting to reduce Catwoman's entire existence to ashes during Ed Brubaker's run on the character in the early 2000s. Black Mask's reign of terror in Gotham's East End was brought to an end by Catwoman, only for Sionis to exact brutal revenge on Kyle's loved ones, including her sister, who he tortured and fed pieces of her dead husband to.
This bloody back and forth was only going to end one way, and in Catwoman #52 by Will Pfeifer and Pete Woods, Selina shot Sionis point blank in the head, killing him instantly.