Widowmaker

Widowmaker is a lonely, cold but flirtatious assassin. She was trained by Talon and experimented on by the Scientist, Moira. Widowmaker killed her husband as a Talon mission and from that point on feel no emotion or remorse for her crimes.

Widowmaker is the perfect assassin: a patient, ruthlessly efficient killer who shows neither emotion nor remorse. Once, her only two loves were dancing and her husband but now, her only joy is found in the moment of the kill. An unstoppable killer, Widowmaker’s crosshairs are perhaps the most dangerous place in the world

Widowmaker does not keep track of the number of people she's killed, and prefers to work alone.[4] She is unaffected by low temperatures