I thought it was strangely coincidental that Metatron’s line here from 10x02 is almost identical to one from 4x20. As you may recall, in “The Rapture” Castiel had been called back to Heaven and forced to vacate his vessel (leaving it without Grace, if you will). Jimmy Novak then returns to his wife, Amelia, and his daughter, Claire, but they are cornered by demons. In the ensuing confrontation, Jimmy is fatally shot and a demon is about to kill Claire. Fortunately, Castiel returns in time to use Claire as his vessel and save the day. Initially, he intended to continue his mission with Claire as vessel, but Jimmy heatedly insists that Castiel take him instead.

In “Reichenbach,” Castiel’s stolen Grace is quickly fading; unless he takes additional Grace or recovers some of his own, he will eventually die. Metatron has said before (previously in season 9 and then again in 10x02) that he could restore Castiel (presumably with some of his original Grace). Obviously, Castiel is opposed to making any more deals, even to save his own life.

However, as we learned in 9x11, when an angel inhabits a vessel, it leaves behind a measure of Grace within the human body. Combine this with the news that the part of Claire Novak is being cast for appearance in season 10, and it seems like there might be more than one way to save Castiel’s life. Is this parallel merely a coincidence? Or deliberate setup for the story? Either way, I’m excited to see what this season will bring for my favorite angel.

Supernatural S10E18 - Synopsis

“Book of the Damned”
FELICIA DAY RETURNS AS CHARLIE — Charlie (guest star Felicia Day) calls Sam (Jared Padalecki) and Dean (Jensen Ackles) to tell them she found the Book of the Dead which could help remove the Mark of Cain. The Winchesters race to her after she tells them she’s been shot by a man named Jacob Styne (guest star Jeff Branson) who says the book belongs to his family and he won’t rest until he gets it back. Castiel (Misha Collins) and Metatron (guest star Curtis Armstrong) take a road trip to find Castiel’s grace but they hit a couple road bumps along the way. PJ Pesce directed this episode written by Robbie Thompson (#1018). Original airdate 4/15/2015. (x)

But let’s be real. If they’re torturing Metatron, it’s because he has answers to Dean’s condition. Metatron has Cas’ grace. Metatron held the power of God and probably knows how to fix this because it was all one big part of his epic story.

And once again, we’re right back at Castiel’s grace being the key to Dean’s salvation.

Still not even remotely over the fact that Metatron:

actively avoided killing Dean when he had the opportunity during their fight, waited to have the chance to stab him on purpose, stabbed him with the angel blade, immediately ran back to heaven, deliberately kept his hands and the blade bloody to show Cas, all because the part of his plan that had to do with killing Castiel was about telling him he’d killed Dean right before and then sticking him too, so that Castiel would die by the blade that had killed Dean, still covered in Dean’s blood.

That creep read too many books all right.