Little is known of the life of Vincent Velcro before he volunteered for Project M ("M" for "Monster") or why he was serving a thirty-year sentence in an army brig. Upon volunteering for six months Velcro was injected with a compound composed of experimental chemicals and blood extracted from the New Mexican Vampire bat. This gave him the appearance of a vampire with their bloodlust and the ability to change into a human sized bat. He, alongside the others changed by Project M, became the part of the military unit known as the Creature Commandos led by U.S. Army Intelligence officer Lt. Matthew Shrieve.
The Creature Commandos were sent on missions no sane unit would touch and became a scary story men would tell each other on the battlefield. At the waning days of the war the Creature Commandos and the G.I. Robot ( J.A.K.E.) were court-martialed for some unstated offense and were given the choice of execution or test flying a experimental spacecraft. They chose the latter, but the ship malfunctioned and was lost somewhere in deep space. At some time the ship was found and captured by the Coluan known as Brainiac and was kept in suspended animation until their release on the newly formed New Krypton. They were returned to the American government and fell under the command of General Sam Lane.
After the death of General Lane, through the manipulations of Maxwell Lord, Velcro and the others were re-assigned to a fake Project Cadmus base in Vietnam. There they fell under the mental control of Lord and were further "altered" by Professor Ivo. Then they were sent after Justice League International in a scheme of Lord's to kidnap Jaime Reyes (the current Blue Beetle). Once Lord and Reyes were teleported from the fight, the Creature Commandos were freed from Lord's control.