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Since Black-Kyurem's move back up to DUber, and the small usage of Darkrai in DUber, I could see Darkrai returning to DOU and seeing some nice niche play in the tier. Dark Void has potential in DOU, don't use it in OU
Hi, while welcome thoughts on tiering, this post doesn’t warrant its own thread. It would have been a better fit for either the metagame thread or the simple questions thread. As a new post generally needs approval, I’m going to lock this thread, and I recommend you read the rules before posting in the future.
But to quickly answer your question, Darkrai has been banned from DOU, as Dark Void’s ability to put two opposing pokemon to sleep was deemed too strong for the tier.