Mantis later joined FOXHOUND and began wearing a gas mask to prevent people's thoughts from entering his mind as well as to hide his burned face. In 2005, Mantis joined FOXHOUND in taking over Shadow Moses island. Mantis also used his powers to get the Genome soldiers to join in FOXHOUND's take over of the island. He didn't agree with Liquid Snake's ideals, the only reason he agreed to take part in the takeover was so that he could kill as many people as he could. During the incident, Mantis took control of Meryl's mind and attempted to use her to kill Snake. Snake was able to stop Meryl and instead Mantis decided to attack Snake directly. Snake is too powerful for Mantis and Snake succeeds in killing him. Just before he dies, Mantis tells Snake how to get to Metal Gear and then remarks on how good it feels to actually use his powers for good.