Cranius is an Un-Man created by the evil wizard Anton Arcane to be the voice of his Un-Men army. When Anton Arcane witnessed the birth of the Swamp Thing, he ordered Cranius to send his Un-Men army to collect the monster and bring him back to Castle Arcane. Cranius led the army to victory, and brought the Swamp Thing across the ocean to his master. Cranius and the Un-Men later attacked the Swamp Thing inside of Castle Arcane after the creature foiled Arcane's plan to take control of the Swamp Thing's body. In the battle, Arcane fell out of the tallest window in Castle Arcane, dashing his body on the rocky mountainside below.
Cranius led the Un-Men army to collect Arcane's body and bring it to his laboratory. Once there, Cranius surgically removed Arcane's brain and placed it inside an Un-Man body. Once Arcane came back to life, he lead his Un-Men across the ocean to America in hopes of finding the Swamp Thing in the swamps of Houma, Louisiana. Arcane found the Swamp Thing there and challenged him to a battle to the death in order to finally collect the Swamp Thing's body. During the match, Arcane and his Un-Men were interrupted by a group of spirits who haunted the land the Swamp Thing and Arcane were fighting on. The spirits emitted psychic signals to Cranius and the other Un-Men, which revealed to them their lowly status. They revolted and attacked Arcane, tearing his body into pieces and burying the limbs in separate graves.
Cranius was next seen almost two decades later leading a large group of Un-Men to take over the reservation of Aberrance, and turning it into Aberrance U.S.A.; a theme park and headquarters for their new corporation UnCorp. Aberrance U.S.A. grew so fast, it quickly became one of America's biggest tourists attractions, even rivaling Disney World. Cranius went under cover as the owner of Aberrance U.S.A., Dr. Von Schadel, and spent his time creating new Un-Men of his own twisted designs. The Un-Men of Aberrance U.S.A. maintained a powerful prejudice towards the local "gaffs" (human beings with peculiar traits and mutations). The Gaffs of Aberrance began to worship Damian Kane, the founder of Aberrance, as a saint, hoping that he would come back to life and punish the Un-Men who invaded the land. Little did they know that Cranius invented a formula called Compound K, that was made from the DNA of Damian Kane. Compound K was meant to preserve severed limbs for later experimentation. Damian Kane was able to rise from the dead through the formula and when he did, he attacked Aberrance U.S.A. and Cranius's Un-Men. Cranius used his psychic powers to lead Agent Kilcrop of the FBI to victory over the Un-Man, Damian Kane.