Arthur "Merlyn" King is an former member of the League of Assassins and a mercenary with a rivalry with Green Arrow reguarding who is the better archer.
Count Werner Vertigo is an Eastern European nobleman who had a device implanted in his inner ear to cure a genetic defect. The device allowed him to manipulate others' perception. He eventually joined Amanda Waller's Suicide Squad.
Constantine Drakon is a Greek mercenary and professional assassin with heightned reflexes, believed to be Metahuman.
Daniel "Brick" Brickwell is a brick-skinned crime lord.
Onomatopeia is a professional assassin specialized in eliminating superheroes, who only speaks through sound effects.
Doctor Light is a scientist who stole an uniform that allowed him to manipulate light. A psychopatic rapist, he was eventually killed by the Spectre.
Deathstroke is the world's greatest mercenary, created in a failed Supersoldier Program developed by the United States government during the Vietnam War.
Cupid is a vigilante obssesed with Green Arrow.
Steelclaw is a mysterious drug dealer and crime lord, secretly the Mayor of Star City Thomas Bolt.
Prometheus is a criminal mastermind who downloads information and talents directly into his brain and nervous system with an advanced helmet.