Clyde was working with Dr. Rarque when they discovered a growth formula that created a pig of tremendous proportions. Rarque thought an invention like this could eliminate world hunger, but Clyde thought of how famous the two men would become. Unfortunately, the pig went wild, destroyed the lab, and delivered a blow to Dr. Rarque that affected his mind in a negative way. The doctor’s research grant was terminated since he was no longer able to work, but Clyde would not let that stop him from getting famous or making a ton of money. He eventually stole some lab equipment from Dr. Benson and set up shop in an old barn to continue his experiments. Eventually, Speedball decided to investigate, and after fighting two giant ants and an enormous snake, came face-to-face with the thief. During a brief scuffle, a giant rat burst into Clyde’s lab and ripped him open before Speedball killed it. Speedball disposed of all the mutated animals in the nearby lake, so there wouldn’t be an investigation that could possibly lead back to Dr. Benson and himself. Clyde was pronounced dead at the scene.
In his haste to cover up the activities of Clyde, Speedball must have mistakenly thought Clyde had perished from his wounds. However, Clyde had returned and orchestrated a major break-out from the Springdale prison, liberating all of Speedball's old sparring partners. He hired the group of thugs to acquire Niels, the cat, because he had the same powers as the Masked Marvel that foiled his plans. An alternate reality Speedball was visiting Springdale when he stumbled upon his former foes as they were hiding out Dr. Benson's basement. Making quick work of the crew, Speedball was momentarily stopped by Clyde, now calling himself Rebound. Speedball and Niels were strapped into a machine that would transfer their powers to Rebound, and Clyde confessed to Speedball that he was the mastermind behind most of the super criminals in Springdale. The experiment was finally started, but a kinetically charged hairball coughed up by Niels caused Clyde's equipment to malfunction, and Rebound had been stopped yet again. He was taken to jail along with his hired flunkies.
