Pokémon Legends: Arceus will give players a chance to catch Darkrai, but only if they have save data from Pokémon Brilliant Diamondand Shining Pearl. Pokémon Legends: Arceus is set in the Hisui region, which is the ancient version of the Sinnoh region from Pokémon Diamond and Pearl, so it makes sense that one of the Mythical Pokémon introduced in those games would make an appearance.
The sinister Darkrai is a Mythical Pokémon with the ability to cause nightmares. It's a member of the Lunar Duo
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