During the climactic confrontation between Venom Snake and Skull Face's forces in the Metal Gear Sahelanthropus hangar bay, Skull Face revealed the true nature of the "Man on Fire" and had ordered Mantis to pit him against Venom Snake one final time. Unbeknownst to either Venom Snake and Skull Face, Mantis was distracted by Eli's presence in a nearby Diamond Dogs helicopter. Favoring Eli's greater sense of hatred over both Skull Face and Volgin's lust for vengeance, Mantis let himself be used as a conduit by Eli to hijack Sahelanthropus. Controlling the Metal Gear under Eli's influence, Mantis turned on the XOF soldiers. Wreaking havoc on Skull Face's forces, the Metal Gear decidedly attacked Skull Face himself, causing him to become trapped under debris. Eli, with the assistance of Mantis, would then focus his efforts on attempting to kill Venom Snake by using the Metal Gear. After a prolonged battle, Venom Snake was able to incapacitate the Metal Gear thus removing Liquid's control over it. Though Venom Snake attempted to destroy the parasite vials containing the English strain, Mantis was able to retrieve one of the vials in secret.