In Japanese folklore, Kitsune along with Tanuki are magical animal spirits.
According to legend, both are capable of shape-shifting and creating illusions to trick people. However, most are simply mischievous and are usually harmless if not angered somehow.
Embedded in popular folklore, kitsune have made appearances in several Japanese works. In Super Mario Bros 3, Mario has the ability to change into a Tanuki by using a leaf power-up (though the suit is called a Tanooki Suit in the game). Mario gains the power to turn into a statue while he is wearing a Tanooki Suit. Sonic the Hedgehog's two-tailed sidekick Tails may be based on the legends of the kitsune. And two Pokémon creatures, the Vulpix and the Ninetales, are undoubtedly derived from the mythical kitsune.