He had psychic abilities, with "mental fingers" able to rummage into the mind of another being. This skill was performed through a machinery which physically linked their heads.
He was hired to discover, in the memories of the terrorist Fenris the Hellbringer, the identity of the instigators of his aggression which contributed to the disappearance of Omega. Just when Viridian unveiled the answer, the Order of the Black Sun teleported into the Question Hall of the Prydonian Chapter and attacked the Chronarchs. Viridian was one of the casualties of the attack. (COMIC: 4-D War)