Approximately 40 years ago, Captain Omen's men began to lay claim to the ocean floor. Over the years, Omen had a son by an unnamed woman, whom he named Filius. He created Aquon to be his secret weapon.
Captain Omen and the Infra-Worlders observed the Hulk until the Hulk busted out of the sub, and had to be rescued by the Infra-Worlders in the process of the Hulk turned back to Banner, and everything was fine for awhile.
Captain Omen was nice enough to send out an oxygen helmet to let him live but then told him that he would have to wander the ocean floor, follow the Infra-World, and obey him, or else he would pump his helmet full of poison gas.
Many of the Infra-Worlders were rebelling against Captain Omen, so they helped him back into the ship. The Hulk fought Aquon, shattering the hull of the Infra-World in the process. Omen had the ship repair itself and pump out the water, but Aquon got sucked outside in the process.
Captain Omen was forced to concede to the Infra-Worlders and bring them to the surface world, where they began to very rapidly die off. He quickly re-pressurized the ship and saved the others still on board, but he left everyone else outside to perish including his son, Filius. Captain Omen took the Infra-World back to the ocean floor.
Captain Barracuda was later shown occupying a base that Omen had once used and abandoned. No further explanation was given.