Obito used Izanagi.
That's all I can say that makes any sense.
But yeah, I so called this in chapter 687's thread that the only way Kakashi could stay relevant is if Obito gave him both eyes, and the Uchiha Kekkei Genki to control it.
Unless Obito royally ****ed up and Kakashi can't turn the eyes off, at which point he'll have to be blind completely unless in a fight.
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