The Mole Man conducted attacks on the surface world by destroying nuclear power plants in the Eastern Bloc, Australia, South America, and French Equatorial Africa, attracting the attention of the newly-formed Fantastic Four in their first adventure. After the group arrived on Monster Isle, he captured Mister Fantastic and the Human Torch and told them his plans to invade every major urban area on the planet via a network of tunnels. When he released a horde of monsters the Human Torch sealed his realm's entrance. The Mole Man appeared to have destroyed Monster Isle in an atomic blast. The Mole Man's Deviant-bred monstrous mutates, collectively known as the "Mole Man's Monsters", include the three-headed Tricephalous, the horned Megataur, and the flying bird-insect creature known only as "Skreeal". The Mole Man also has a group of superhuman allies called the Outcasts.