On Supernatural Season 13 Episode 13, Lucifer found a confidant in an angel going by the name of Jo. When Lucifer learns of a woman who is healing people instantly, he realizes she's an angel. He initially goes so he can take her grace, but she makes a deal with him. If he keeps her alive, he can feed off her grace. Lucifer takes her up on the deal, and the two of them end up bonding. 

Meanwhile, Sam, Dean and Castiel call upon Donatello to help them read the demon table so they can possibly find a way into the other world to save Mary, and Jack. While Donatello is trying to wrap his brain around the table, the guys are able to track down Lucifer to a motel he is staying at with Jo. Unfortunately, the guys lose the battle with him because his powers were fully restored thanks to the grace he had been taking from Jo. 

Jo and Lucifer are able to escape, and they make a deal with a few of the angels still left. Lucifer promises he will help them get more angels, but he needs to be back in power first. The angels agree, and they head to heaven where Lucifer takes over. 

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