Darkrai

Darkrai using Dark Void

Darkrai is The4everreival's 14th favorite Pokemon of all time. He can lull people to sleep and make them dream. He is active during nights of the new moon.

Darkrai chases people and Pokémon from his territory by causing them to experience deep, nightmarish slumbers.

Countdown To Chang's Guide To The Galaxy

Lincoln and Lydia dream of Full Moon Island and they run into Darkrai and capture it. With it, they use it in tow. Lydia  arrives in Veilstone City and she settles on using Darkrai. Lydia uses Darkai to put in work on Charon and the  Team Galactic Grunts with Lincoln, Dawn, May, and Doc as she intends to free the Lake Trio with Lincoln and Dawn respectfully.

She also uses it to help deal with The Smoking Man and The Primal Creation Duo

Gallery

Who's that Pokemon? (X and Y edition)