The Winchesters' Villain Messes Up Supernatural Canon Pretty Badly
Add that to the huge list of the ways the prequel has already trashed the canon.
The main villain in The Winchesters ( at least so far) is the Akrida — a hivemind led by the queen that can possess human bodies and is invincible to weapons, so it's virtually impossible to kill it. In episode 7, the queen herself confirms that basically nothing on Earth can kill her.
While it sounds like pretty much every single other villain on Supernatural, there is something inherently wrong with the queen's confidence about how "nothing" can kill her. After all, Supernatural has established that angels and demons are not killed when their host dies, but using a colt or an angel blade against them does the trick, and kills both.
So, it appears that The Winchesters messes up with the Supernatural canon once again by having the Akrida queen claiming that nothing can kill her — or we are yet to know more about the villain, and the show is on track to explaining itself.
Fans, who are already getting used to the prequel not caring much about the canon, believe that it could go both ways. After all, the Akrida queen could simply not know about colt, angel blades, or any other superior weapons from Supernatural even existing, so that technically makes her statement about being invincible true.
"She seems to be very powerful, an archangel level powerful. Neither the colt or angel blade work on archangels, so yes, nothing on this earth can kill her," Redditor PSofSuddenlyGivingaS suggested.
The uncertainty around the Akrida queen is not the only questionable thing about The Winchesters. It is still unclear how the prequel co-exists with the original show, given that Supernatural establishes a dramatically different John and Mary storyline. As of now, the prequel has not openly indicated that its events are takins place in some sort of an alternate universe, but neither has Jensen Ackles, the series' executive producer, confirmed that The Winchesters retcons Supernatural.
Currently, the prequel is on a short hiatus, with The Winchesters episode 8 set to premiere on The CW on January 24.