Meeting the Turtles and Vs. Rocksteady and Bebop
Mondo Gecko was created by Old Hob for his mutant army using a sample of Splinter's mutated blood and mutagen stolen from Stockgen. Mondo meets Splinter and the Turtles and quickly grows a liking to Michelangelo since their personalities seem about the same. Mondo engages in his first battle when Pigeon Pete mistakenly believes Rocksteady and Bebop to be friends, and brings them to the alleyway Old Hob and the Turtles are having a meeting.
To try and stop a fight from happening, Old Hob attempts to reason with Rocksteady and Bebop asking them to join his mutant army, pointing out that Shredder is only using them as slaves. When Rocksteady mentions that they're both half-human, Hob shoots them both immediately and the fight begins. Mondo attacks Bebop shooting him in the face but is hit hard by Rocksteady's sledgehammer. Mondo then follows Splinter's plan to cut down an electrical wire and shock the two brutes. This puts them down but far from out to everyone's surprise.
The battle comes to a close when Old Hob orders Herman the Hermit Crab to "bring the noise". Herman unleashes a furious missile barrage that deliberately misses the two behemoths, but instead destroys the foundation of a building behind them, burying them underneath tons of rubble and the two groups leave as the victors.