FOX's chief medical officer. She is in charge of keeping Null under control and monitoring his culture tank. Ursula, FOX's precog, is Elisa's alternate persona.

Elisa gained ESP abilities when she was exposed to radiation in a nuclear disaster in the Ural Mountains in 1957. She tried to stop Gene's madness, but was defeated by his Zero Shift. In her last moments, she delivers a prophecy of Naked Snake's future.