Albert Wesker (Resident Evil 4)

Every time a viral or B.O.W. incident occurs across the globe, one man always seems to be there, either standing at the forefront or controlling things from the shadows. That man's name is Albert Wesker.

Upon learning of the mind-altering properties of certain parasites in Europe, Wesker hatched a plan to obtain a sample of these "Las Plagas" from the Los Illuminados cult. Then, in 2004, he sent Ada Wong and Jack Krauser to infiltrate the cult and return with a sample of the control Plaga. His best-laid plans went foul, however, as Krauser was defeated by Leon, and Ada betrayed him, bringing him a sample of an inferior subordinate Plaga. Undeterred, Wesker later acquired a dead control Plaga through alternate channels.