666 (Kingdom Come)
666 was a psychotic, violent "superhero" of the mid-21st century. A "tattooed, self-mutilated man-machine of destruction," he fought against such villains as the Slaughter Brigade. Once most of the villains were eliminated, he spent much of his time battling other vigilante "heroes" for the sheer desire to fight, uncaring of however many people or places he threatened in so doing.
666 was incarcerated in the Gulag with other violent so-called "heroes," but proved a problem inmate up to the mass escape and riot provided by Captain Marvel. 666 was slain with many others when a nuclear warhead was dropped on the battlefield where he (and his fellows) battled the Justice League of the World.