Phantom Zone
In his first appearance, Jax-Ur escaped from the Phantom Zone and posed as a super-powered version of Jonathan Kent. Superboy eventually sent Jax-Ur back to the Phantom Zone. Most of his later Silver Age appearances show him in his ghostly Phantom Zone form, except during rare escapes. He was often depicted plotting against Superman with fellow Phantom Zone inmates General Zod and Faora Hu-Ul. Although he possessed typical Kryptonian super-powers when on Earth, the out-of-shape Jax-Ur was no match for Superman in combat.