Xal-Kor was from the 4th dimension. He claimed his race was a group of cats that went into "hyper-evolution" (giving them human-like appearance and level-intelligence). Xal went to Earth to stop the "Rat people" known as "Rodentites" (who had similar powers as him) from conquering the Earth. Using his shape shifting, he took a job as a reporter named Colin Chambers (possibly a reference to Clark Kent). His Lois Lane-like secretary, Ann Rhoden, was really one of the Rodentites, but he didn't know this nor did she know that he was really Xal-Kor. He would often battle the Rodentites and usually acted kinda ruthless towards them (in his first appearance he killed two of them). But, he couldn't expose them because it would incite panic. He never actually completely stopped their plan (in every story there would be like a dozen left alive).
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