Dark Void(ダークホール Dark Hole) is the signature move of Darkrai. In the games Pokémon Diamond, Pearl, and Platinum (where it is seen), it sends the foe into a dark vortex and puts it to sleep. It has 80% Accuracy, 10 PP, and falls under the Status category. In a Double Battle both opponents fall asleep. This move is Dark type.
In the Anime
In the anime, Darkrai forms spheres from his hands and throws them in all directions, causing whomever and whatever they hit to sleep. Like the games, the targets are put to sleep, and Darkrai's Bad Dreams ability comes into play, causing damage to the opponent. Only two Pokémon can learn this move: Darkrai, through level up, and Smeargle, through its signature move, Sketch.