Supernatural's Dean Winchester may have the Mark of Cain, but that doesn't mean the Father of Murder won't make a reappearance sometime in the future.

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Cain (Tim Omundson) originally appeared in season 9's "First Born" in order to transfer his mark to Dean and turn Crowley on to the location of the First Blade, but thanks to a promise made between the hunter and the demon, there's a very good chance Cain will be popping by again soon.

Tied of his life and retired from the world of killing, Cain attached a caveat to his deal with Dean. In exchange for the Mark (which is not particularly a gift in and of itself) and the First Blade, Cain has asked the elder Winchester brother to kill him when he's done dealing with the problems of heaven and hell.

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Considering Dean currently has the desire to kill everything that moves, he should be more than willing to fulfill his half of the agreement. Unless he decides he would rather ask Cain take the mark back.

Whatever Dean's decision, Omundson has confirmed that his work on ABC's Galavant will not prohibit him from making another appearance on the CW drama.

"Even w/ another show, Tim can still come back as #Cain - he is 2 badass 2 replace," a fan tweeted the actor on Tuesday, to which Omundson replied "Thats the Plan!"

Do you think Cain will wind up helping Dean? Tell us in the poll below!

Supernatural airs Tuesdays at 9 p.m. ET on The CW. Click the video below to see a preview of the season finale, "Do You Believe in Miracles."