(Dean Buscher / The CW)

TV Line reports Supernatural co-showrunner, Andrew Dabb is teasing the “big bad” for the drama’s 13th season on The CW — and it’s not Lucifer’s son, Jack. According to the report, Dabb said, “It’s an old — let’s call him friend — who we have not seen for many years.” Reporter Vlada Gelman floated her own theory about who it may be. Check out some unspoiled speculation, after the jump.

The season 12 Supernatural finale, “All Along the Watchtower,” was a deadly one, with Crowley (Mark Sheppard) finally stepping up and sacrificing himself, and Lucifer (Mark Pellegrino) killing Castiel (Misha Collins) — at least temporarily. Sam and Dean (Jared Padalecki and Jensen Ackles) also had to watch as Lucifer shoved Mary Winchester (Samantha Smith) into the rift that leads to a post-apocalyptic world, in which Sam and Dean were never born. At least Mom took the devil with her. Regardless, the boys will have a lot to overcome in season 13.

Supernatural Season 13 Speculation

Here’s more from Dabb, via TV Line about Supernatural‘s lucky 13th season on The CW:

“[Lucifer’s child] Jack is not the biggest threat they are dealing with,” executive producer Andrew Dabb revealed during a San Diego Comic-Con interview. While the EP declined to identify which evildoer gets that special title, he hinted that “it’s an old — let’s call him friend — who we have not seen for many years.”

The mysterious foe “probably is not currently in our world,” Dabb added. “He [is] from the alternate world,” where some of the show’s deceased characters are still alive and kicking.

Could the Big Bad be the archangel Michael, who was trapped in Lucifer’s cage during Season 5 and, last we heard, driven mad? “I’ll plead the fifth on that one,” Dabb responded.

Whoever the returning player is, he “will create many, many problems” for Dean and Sam.

Supernatural likes to inflict maximum pain on Sam and Dean. While their half-brother, Adam (Jake Abel), did serve as Michael’s vessel, Sam and Dean never had a significant relationship with him.

How painful would it be if Bobby Singer (Jim Beaver) was their biggest threat? We did see Bobby alive in that alternate universe, but Dabb said we haven’t seen this character in “many years,” which probably rules him out. Bobby did say Rufus (Steven Williams) is still alive in that reality, though.

For all we know, it could be Balthazar (Sebastian Roche), Gabriel (Richard Speight, Jr.) or one of the other angels. Any way you slice it, we will still have to wait a couple of months. Supernatural season 13 premieres on The CW, Thursday, Oct. 12th at 8:00pm ET/PT.

What do you think? Whom do you hope to see as the villain in the 13th season of the Supernatural TV series?