A/N: OK, the whole "Cas is god" finale plot-point was poorly set-up and ultimately stupid. The whole finale (inclusive of the final 3 episodes) was so stupid I can't believe they actually let those people put on a TV show. They obviously crammed a season's worth of storylines into those last 3 episodes, instead of giving us a fully realized, coherent arc for 22 episodes. But - I had an idea how the boys might get away from "Blasphemiel" (as I've heard him called) and so I had to include him in this story. (Personally, I think their escape will be as abrupt and 'deus ex machina' as it was in the S5 premiere.)
The Wall fell.
Cas knew he had to get the Winchesters off of his trail or he'd never accomplish his plan of absorbing the souls from Purgatory. And he knew that the only way to get them off his trail, even temporarily, was to harm Sam. He hated to do it – Sam had proven a friend over and over again - but it was the only way. If he hurt Dean, well – the Winchesters travelled well-armed these days and that included the angel-killing knife. If Cas harmed Dean, Sam would slaughter him on the spot.
If Sam was hurt, Cas knew, for Dean Winchester all things would stop. If Cas ruptured the Wall in Sam's head, Dean would get him someplace safe – Bobby's no doubt – and weigh his options while guarding and tending his brother. He would act, there was no doubt of that, but he would act after seeing to Sam.
If Cas did the equivalent physical and emotional harm to Dean – Sam would slaughter first and tend to Dean after. Dean had anger, Sam had rage.
So Cas had no choice.
The Wall fell.
Dean wasn't surprised when Sammy appeared in the bizarro-world reality of Cas-gone-darkside, even though it was a good ten hour drive from Sioux Falls, South Dakota to Bite Me, Kansas.
He was relieved that Sam was upright and functioning, that for all of everyone's dire predictions of mental & emotional paralysis, Sam was alert and oriented, and hunter enough to realize what was going on and give killing Cas his best shot.
But Dean wasn't surprised that when the Wall fell, Sam stood. The official Winchester Motto after all was 'survive against all odds', and the unofficial one seemed to be, 'prove your enemy wrong just before you gank him.'
The Wall fell, and Sam stood.
Only now it looked like at any second Sam would quit standing and go face first on the floor. Dean needed to get to him, Dean was going to get to Sam, douche-angel-god or no douche-angel-god in his way. Bobby had to know that Sam was Dean's priority and when Cas intoned, 'I am your god', Bobby drew the fire to himself.
"No, you're not. You're a boy who thinks he's a man just 'cause he can put on his Daddy's galoshes."
When Cas fixed his attention on Bobby, Dean fixed his on Sam. And thank God - well, thank whoever - Sam was fixed on Dean. Pale and unsteady, but looking right at Dean. So Dean held out his hand, motioning Sam to come closer, wanting - needing - Sam behind him.
"That is insolence." Cas growled to Bobby.
"No, it's a little something called the truth." Bobby growled back.
"You will worship me or I will kill you."
And that's when Dean got his first Sammy-surprise: instead of seeking safety behind Dean, Sam waved off Dean's motion to stand behind him as casually as if Dean had only been offering to hold his cup of coffee for him while he answered the phone. Instead of standing behind Dean, instead of face-planting in the sticky mess of what was left of Raphael, Sam looked at Cas and actually snorted in disdain.
"Go ahead. Kill us. Maybe you'll be the first one to ever make it stick."
"I am your god." Cas answered the challenge, eyes blazing, "You will worship me."
"No. We won't. We don't worship smug-faced, snot-nosed douchebag dicks hopped up on their own self-importance."
Dean couldn't help thinking, 'that's my boy.'
"How dare you speak to me that way." Cas said.
Sam took a step closer to him.
"How dare I? You're the one who knocked the Wall down. You're the one who let free the old Sam, and the Sam who survived hell -." He took another step closer to Cas-on-crack and Dean was absolutely proud of the gleam he saw in Sam's eyes. "- and you released the Sam who just doesn't give a damn."
"I will kill you." Cas still tried, but he was sounding a little less sure of himself. Sam only huffed like he was disappointed.
Castiel lifted his hand and Sam lifted his chin and Dean thought - if this was it, at least they were going out together. But Sam had one last parting shot to Castiel.
"Go ahead, kill us. Just remember - we have yet to stay dead. And when? was the last time we didn't ultimately kill anything we wanted to?" Sam's mouth half curled into an ugly smile. "So, yeah – you kill us. But we're coming back pissed."
Castiel considered Sam remarks.
The Wall had fallen.
Yet Sam had stood.
Sam shouldn't be standing. He shouldn't even be conscious, yet he was not only conscious, he was upright, lucid, and so determined to stand with his brother that he'd endured the desperate drive here by himself.
Determined to save Dean if he could. Determined to avenge him if he had to.
Dean had anger, Sam had rage.
They both had continuously had some higher power – God or Death - intervening for them at critical moments of infirmity or death.
Sam and Dean had died so many times, Castiel no longer had an accurate count. Yet they stood before him now, as alive and as formidable as only these Winchesters could be.
Because of God. Because of Death.
Because of their persistent refusal to consider death as permanent or failure an option.
Castiel had absolute power – but not power enough to challenge God or Death in a close contest. And that's what he'd have if he dispatched the Winchesters right now, he was sure of that.
He lowered his hand.
"You should be grateful for my mercy." He said. He told himself they wouldn't realize the truth. "Flee, or die."
Bobby looked disbelieving. Dean looked distrustful. Sam practically spit out his contempt.
"Yeah, that's what I thought."
In less than a moment, Dean and Bobby moved forward to stand with Sam, one on each side, each of them glaring at Castiel as though daring him to make another move.
The Wall fell.
Castiel removed himself to a safer location.