Later in the series, the Mutanimals were ambushed and gunned down by Null's band of half-dead Cyborgs called the Gang of Four. Slash had not been with his friends at the time, and when the turtles, along with Ninjara, and the future counterparts of Donatello and Raphael were investigating the massacre Slash initially thought the turtles and their friends were responsible and attacked them. Once convinced that the turtles were not to blame, Slash joined them in their investigation. The Gang of Four brazenly confessed to killing the Mutanimals when the two groups fought, sending Slash into a rage. Although he had slain his friends's murderers (with some help), the revelation that Null was behind the attack meant that Slash's quest for vengeance wasn't over.