Chalo was a violent revolutionary opposed to the Honduran government under the command of Raphael. He helped capture Rogelio Duran, Dr. Daniel Jackson, and Dr. Bill Lee. Later, when Raphael activated the Ancient healing device, he urged him to turn it off and Raphael shot him, killing Chalo immediately.
Chalo's dead body was exposed to the energy and it was reanimated with Raphael and his fellow mercenaries attempting to stop Chalo but with little success. Chalo then began to kill his friends until he was blown up with a grenade by Burke. (SG1: "Evolution, Part 1", "Evolution, Part 2")