Years inbreeding, practicing foul rites and consorting with otherworldly denzins has led to the birth of more than a few malformed, degenerate members of the Whateley family.  Malrog is one of these "touched cousins".  Froglike in appearance, Malrog was kept hidden from the citizens of Gomorra in the Whateley family manor.  

Malrog made his first appearance when the Sioux attacked the Whateley family manor, and he slew Little Mountain.

Later, when the agency attacked the manor, Malrog found setting explosives in the basement.  Malrog attacked and took a .38 bullet in the leg, but the distraction bought time for the other creatures in the basement, forcing "Boom Boom" to detonate the explosives, killing the creatures as well as himself.

Malrog somehow survived the explosion, and once again appeared, this time outside the manor and attacked Captain Sim of the Maze Rats.  Sim, who was distracted by the death of his bodyguard, Sun Shu-Jen, didn't see the attack coming, but was saved by Freddy "Fast Hands" Groves, who broke Malrog's neck with his bare hands.