Darkrai

Darkrai (ダークライ, Dākurai) is a Pokémon from Pokémon Diamond and Pearl. It is one of types of Pokémon from the series of the same name. It is a mysterious ghost-like Pokémon who even stared in a movie called Pokémon: The Rise of Darkrai. It also appears in Super Smash Bros. Brawl as a trophy.

Description
Darkrai are genderless. They can travel quickly by turning into a shadow, and perhaps its most notable ability is being able to trap people's nightmares. Another Pokémon named Cresselia is capable of reversing this effect. One move that is exclusive to Darkrai, called Dark Void, is best used in team battles as it is capable of making both opposing Pokémon fall asleep. In Diamond and Pearl, Darkrai is found on an island called Newmoon Island.

Super Smash Bros. Brawl
Darkrai was intended to appear in the Wii video game Super Smash Bros. Brawl as a Pokémon that appeared out of a Poké Ball, but for whatever reason it was taken out of the final installment. However, Darkrai still appears in the game as a collectable trophy that will be placed in the Pokémon series section.

Trophy Description
''A Pitch-Black Pokémon. It becomes active on nights of the new moon. This legendary Pokémon has the power to lull people to sleep and fill their heads with dreams. Proverbs say that Darkrai will make people have terrifying dreams on moonless nights. A Dark-type Pokémon, Darkrai uses the Dark Void move, along with Embargo, which stops foes from using held items.''