When Bizarro III found himself infused with radiation from a blue sun, he developed the ability to replicate himself as well as create other "Bizarro" lifeforms based upon likenesses of people from Earth. He used this power to populate a cube-shaped planetoid dubbed Bizarro World within the blue sun star system. One of the many duplicates that he created was a Bizarro version of Superman's adversary Mister Mxyzptlk. Bizarro imprisoned Mxyzptlk inside of his Fourtriss uv Bizarro along with several other known foes. Mxyzptlk pleaded with Bizarro to allow him to return to the 5th Dimension, but Bizarro decreed that he could not go home unless he spoke his name backwards. Mxyzptlk told him that such a demand was unfair as he did not know how to spell.