Victor von Doom was Project Cadmus' Chief Scientist. He assisted in experimenting with cosmic-ray shielding from a secure base on Earth while the future Challengers of the Fantastic monitored progress from a space shuttle. Not content for his friends to steal all the glory, von Doom deactivated the shielding and fled as the shuttle crashed on Earth.
Doctor Doom was obsessed with unlocking the genetic secrets within the fallen alien creature called Doomsday (who was defeated by Speed Demon). During Doom's examination, a bone fragment from the monster exploded in his face. The swiftly replicated DNA of the war-like monster transformed the handsome genius into the grotesque Doctor Doomsday.
Doctor Doomsday leads a nefarious band of villains who have been promised absolute power by Thanoseid if they stop the Earth's heroes from interfering with his plan. He was the one responsible for the death of American Girl (partner of Super-Soldier).
All the powers of both Doctor Doom and Doomsday, including evolutionary adaptive powers, regenerative capabilities, immortality, superhuman strength, stamina, endurance & agility. He also had Doctor Doom's incredible intellect & technological suit of armor.
All the abilities of both Doctor Doom and Doomsday.