Bebop and Rocksteady also appear (first in human form) in the IDW comics, where they also work for the Shredder and the Foot Clan. In their first appearance they were helping the mutant Alopex, find the secret hiding place of the Ninja Turtles, but by the distrust of Raphael they were eventually thwarted. Finally, both voluntarily adhere to the transformation to their mutant forms, in order to join the ranks of the Foot
Their origin was finally explained in their villain micro. Rocksteady was a gang member. After he and his buddy Bebop were kicked out of their gang, they joined the Foot Clan and defeated a bunch of other gang members for the honor to become mutants. Rocksteady became a mutant rhino while Bebop became a mutant warthog. After screwing up a job and thinking Karai to be dead Rocksteady suggests that since Karai is dead, they return to Foot Headquarters and just say that she deserted. Karai isn't dead, however, and has overheard the entire mutinous conversation. She sends a bunch of Foot Ninja to kill them. However, Rocksteady and Bebop defeated them and ask for a second chance. Karai than decided to keep them due to their brute strength.