What is Mxyzptlk?
1.
A magical being from the 6th Dimension. He is a pest, and his pranks can become very dangerous. One of the ways to send him back to his own dimension is to trick him into saying, spelling, or otherwise revealing his name backwards: KLTPZYXM. Once banished, he may only come back after 3 moons' passing. If you get him to reveal his name backwards, twice in a row, he will be stuck in his dimension for eons.
Superman banished Mxyzptlk back to his own dimention several times, only to be pestered by him again three months later.
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