He's seen Cas flick through a dozen different identities. Soldier, traitor, fugitive. Complete dick, best friend. Hunter, junkie, attacker, leader, subordinate, saviour. Angel. Human. Angel.

And now this.

Don't ever change, he said to Cas once, standing on the edge of a dark road, gratitude and relief washing euphorically over him. Well, that was fucking ironic.

He can see the terror scrawled over Sam's face - oh God, I just stabbed him, he's going to eviscerate me - and the frozen, caught-in-the-headlights expression on Bobby's, but Castiel's shows only a calm unconcern and that beatific, twisted smile. It's like a distorted reflection, a cruel parody of the quietly proud smile Cas used to get when he'd deus-ex-machinaed Dean out of yet another certain death; there's pride there, yes, a bright brilliant pride…or triumph, or joy, maybe. Dean doesn't think the right word to describe that smile has been invented yet. But the searing intensity with which Cas used to focus on anything that caught his attention is gone entirely; those eyes point at Dean, at Sam, at the blade he's just pulled out of his own back, as if they're made of glass, so inconsequential that he can barely even see them, and all Castiel's concentration is converged neatly on himself.

Oh, Cas.

Dean thinks of the now-nonexistent dystopia that Zachariah showed him, this is how the world ends, and it's weird how much he's reminded of high-as-a-kite Cas now. The spaced-out expression, all that attention and focus turned inward, the complete disconnection from who and what he used to be; sure, he's tripping on power and souls and God knows what else instead of amphetamines (and God knows what else) but the end result is freakily similar and, shit, maybe the world's actually going to end like this. Dean has no idea what Castiel's going to do. All bets were off the second he reappeared with that empty jar.

Bow down and profess your love unto me, Castiel said, and it doesn't even sound like him, and now the three humans are standing in a petrified circle around the smiling angel who thinks he's God and, right or wrong, has the firepower to back it up. None of them are quite able to make the first move, cast the first dice, decide whether they're going to bow down unto their friend and reinforce his grand delusions, or make a stand and get turned into the proverbial frog-in-a-blender for their trouble.

You know, Dean thinks to himself, the first coherent thought he's strung together since Castel declared himself to be God, for anyone other than the Winchesters, that would sorta be an easy decision.

After that he retains some lucidity, and notices that Sam and Bobby are both staring frantically at him. Probably they're still irrationally thinking of him as Castiel's keeper or something, but joking prayers are one thing and Dean has no idea what to do in the face of this much power and this much crazy.

Bow down and profess your love unto me, your Lord, or I shall destroy you.

It figures that the choice gets laid on Dean.

Bow down, or I shall destroy you. And if they do bow down, maybe he'll let them live and skip off to destroy someone else.

Fuck, Dean thinks. Castiel's eyes are blue and bright and vaguely expectant, and Dean's shoved between a rock and a hard place, as the cliché has it.

This is his fault. He could have stopped Castiel. Maybe if he hadn't abandoned Cas just when he was starting to lose it, he could have kept Cas on the path of sanity. Maybe with some support from his friends, Cas could have dealt with this much power without going completely insane.

I'm sorry, Cas. Castiel looks at him and Dean wonders whether he can hear what Dean's thinking. God's omniscient, right? Dean isn't really sure whether that applies to a megalomaniac angel, but there's not a lot that would surprise him right now.

He looks into his friend's eyes and silently pleads for the old Cas, who'd let the souls go, bow his head in responsibility and do what has to be done. Who'd make sarcastic comments, tilt his head and hold people's stares for slightly too long.

Bow down and profess your love unto me, your Lord, this thing said. This is someone else entirely.

Dean suspects, and it terrifies him, that this smiling, distorted thing with Cas' face is here to stay.