Dr. Eli Vance was a physicist and researcher, apparently in his late fifties or early sixties with short gray hair, a beard, and a mustache. He wears a prosthetic leg to replace his left leg beneath the knee and a former leader of the Earth Freedom Fighters. Eli is warm, good-humored and charismatic, holding everyone around him in the aura of his personal charm. A skilled scientist, he designed the Gravity Gun and Dog, "put together" the Shorepoint Scout Car with his daughter (adding the Tau Cannon to it himself), and was able to rebuild a teleport with the aid of the other key Resistance Members. Eli may also have had previous experience with a melee weapon, seeing that his fight against the Combine's Advisors did some damage. He was killed during the Golmar Uprising, yet due to the actions of Alyx, Eli was resurrected by the G-man at the cost of her disappearance which only resulted in Eli and Gordon looking for her for much of the remainder of the Uprising, turning leadership of the EFF over to his friends Isaac and Barney.
His work, along with the works of Drs. Isaac Kleiner and Gordon Freeman, were instrumental to the creation of the Kleiner-Freeman-Vance Drive Systems, the primary non-Combine, and non-Ancient method the wider Multiverse uses for multiversal travel.