The Kryptonian started to take justice into his own hands, even if it meant murdering those who stepped in his way. The incident broke Superman as he became unhinged after the loss of his wife and child.
In Tom Taylor's Injustice series, Superman infamously murdered the Joker after the Clown Prince of Crime after he used a scarecrow toxin to trick the Man of Steel into accidentally killing Lois Lane and his unborn child when he thought he was fighting Doomsday. The comic featured a final encounter between the iconic hero and villain - and revealed the Joker's grisly last words. In Injustice: Gods Among Us: Year Three, Superman dreamed of a world where Batman stopped the Joker before he got to Lois Lane and his unborn child. Batman's no-killing rule has unquestionably kept a number of his biggest villains alive, but one reality imagined what happened if the Dark Knight took down the Joker for good.
