Darkrai

To protect itself, it afflicts those around it with nightmares. However, it means no harm.

Poke-BODY — Darkness Aura: If you have Cresselia in play, each of Darkrai's attacks does 20 more damage to the Defending Pokémon (before applying Weakness and Resistance).

Hypnoblast (60): Flip a coin. If heads, the Defending Pokémon is now Asleep.