A brilliant youth, Harmon was selected as a candidate for the Super Soldier Project that created Captain America. He was ultimately not chosen due to his hemophilia.
He would spend the rest of his life studying genetics and super powers, researching biochemistry with Howard Stark. He would also teach Reed Richards - the future Mr. Fantastic.
He founded his own corporation called GeneTech to continue his expirements and research. He would create the super team Psionex, but they were all psychologically damaged and were not the force for good he was trying to create.
He also saved the irradiated soil in the aftermath of the Fantastic Four's battle with cosmic-powered Terrax. It seemed that his power and sentience remained. In a battle between the New Warriors and Psionex, Harmon attempted to take the power of Terrax for himself. But Terrax used this oppurtunity to reform by taking Harmon's body, killing him in the process.