The Empty will return to Supernatural for its upcoming final season, providing another big cosmic entities for the heroes to contend with.

TV Line spoke with Supernatural co-showrunner Andrew Dabb about the deal Castiel made with The Empty last season, and Dabb teased how that will play out as the show -- and character -- head towards the end.

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"[T]he last thing Cas is worried about right now is. But it is something that’s going to come back for us this season. As we saw at the end of last season, The Empty is there. The Empty is one of our probably four cosmic players in this universe. He’s going to have a say."

When angels, demons, and monsters finally die, they go to The Empty, both a void and a being itself. Cas made a deal with The Empty when it tried to takeover Heaven, and it looks like that will be a major plot point in the final season. And given the Winchester's history of breaking deals with powerful creatures, expect a fight.

Along with The Empty, the Winchesters will also be squaring off with God, aka Chuck. On top of that, the Darkness will return to Supernatural, yet another of the cosmic players Dabb teased in his comment.

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Returning Thursday, Oct. 10 at 8 p.m. ET/PT on The CW for its final season, Supernatural stars Jensen Ackles, Jared Padalecki, Misha Collins and Alexander Calvert.