User blog comment:BigBadSquid/PE Proposal: Darkrai (Mystery Dungeon)/@comment-27131953-20191108223844

A very easy yes. He is responsible for plunging the world into paralysis, killing off several pokemon in the process, and corrupting Dialga, the keeper of time, to ensure he would maintain the power he gained from the darkness. He's psychologically manipulated the two heroes into giving up their lives in the hopes that the world would be saved, prepared to plunge the entire world into a nightmare, doing it all without any regret or any redeeming qualities whatsoever. And simply because he lost his memory doesn't mean he wouldn't return to his evil ways if he regained his memory: an example of this would be Light Yagami, who momentarily lost his memory and regained his former personality and empathy, but upon regaining his memories, he became even more depraved and maniacal. Point is, based on what we've seen, Darkrai would likely try to resume drowning the world in darkness if he remembered his past.