Mister Mxyzptlk

Mr. Mxyzptlk (pronounced /mɪksˈjɛzpɪtlɪk/ ahd: mĭks-yĕzʹpĭt-lĭk or /mɪksˈjɛzpɪtəlɪk/ ahd: mĭks-yĕzʹpĭt-l-ĭk), sometimes called Mxy, is a supervillain imp who appears in DC Comics' Superman comic books.

Character History
"Mister Mxyztplk" was introduced as an imp from the "fifth dimension". Not being bound by our physical laws, he can do things that seem to be magical. In his first appearance, Mxyztplk wreaks havoc across Metropolis by using his powers to pull all manner of pranks. What's more, he destroys Superman's worldview of himself. Mxyztplk jumps out a window, fooling Superman into thinking Mxyztplk is committing suicide. When he appears unharmed, an astonished Superman exclaims "I-I thought I was the only man who could fly!!" Mxyztplk soon tells Superman that he is a jester in his home dimension, explaining why he uses his powers to play practical jokes.Mxyzptlk later has his powers temporarily stolen by the Joker; interested in seeing how somebody else would do at his job, Mxyzptlk intends to give the Joker only 1% of his power. The Joker tricks Mxyzptlk into revealing his secret imp name and thus acquires 99% of Mxyzptlk's power, leaving him mostly powerless. The imp is also unable to remember what to do to break the chain of events that daily culminates with Superman being dragged back to Arkham Asylum by Bizarro. Fortunately, Mxyzptlk is able to reveal the truth about the world to Superman, who, despite his current lack of faith in himself — caused mainly by the fact that not even Lois Lane believes in him in this world — manages to find the power to defeat the Joker. Superman realizes that, for all his power, the Joker still cannot erase Batman, as the Joker defines himself by his constant opposition to the Dark Knight, Superman manages to shatter the Joker's control of reality. However, Mxyzptlk saves some of the Joker's creations and transfers them into the 'real' world, including Scorch, Gorgeous Gilly, Ignition (he was actually not of the Joker's creation), and the new Bizarro.

Powers and Abilities
Mr. Mxyzptlk has access to fifth-dimensional technology that to third-dimensional beings may as well be magic. His abilities are only limited by his willpower; for example, if he wanted to turn Superman into dust by snapping his fingers, it would happen. His only apparent weakness is the ability to send him back to the fifth dimension by getting him to speak his name backwards, made easier by his gullible nature, and it is only a temporary deterrent. In addition, Mxyzptlk never uses his powers in a deliberately malevolent way, since he would get bored very quickly. He tends to use his powers in ways that are more annoying than anything else.A point as to the nature of Mr. Mxyzptlk has been raised in Batman #680. Batman asks his 5th Dimension counterpart Bat-Mite if he is really an imp from the 5th Dimension or just a figment of his imagination, to which Bat-Mite responds that the two are one and the same.

In other media
In Batman: The Animated Series, Mr. Mxyzptlk briefly appeared as a silent, animatronic toy created by Dr. Karl Rossum in the 3rd season episode "Deep Freeze". His design is identical to the Silver Age version, and he was seen riding on a flying carpet. Bat-Mite, Streaky the Supercat, and Krypto the Superdog can also be seen.