Author's Note
I'm primarily a spn fic writer, but the idea of this crossover intrigued me so I thought I'd share it over here as well. Borrowed a bit of canon dialogue for this, which parts will be obvious if you've seen the episode recently. this is also definitely one of the crackiest things i've ever written. and yet also not.
Abandon All Hope
They were fucked from the moment Cas disappeared, even if none of them were going to admit it. They were already down one Element, though Sam tried. He spent countless hours with those gems laying haphazardly at his hooves, pouring every ounce of magic he had into spell after spell. Finally, they’d given up. If there was an Element of Magic, it wasn’t appearing to them. They had five Elements for five wielders, and that would have to be enough.
And at the end of the world, it was even something to joke about.
(“Jo, swap with me. I’m not wearing this crap.”
“Dean, that’s not how it works.”
“Laughter is a filly’s power. Give me Honesty.”
“It’s not my fault the rock thinks you’re a liar- Hey! Let go!”
“Dean, Jo, not make me come over there and separate you two.”
“Yes, ma’am.” “Sorry, mom.”)
They were such dainty, pretty things. Not fit for roughshod ponies like them, not even Jo, no matter what Dean said. Traditionally, from the lore Sam had dug up, all the mortal wielders before had been mares. That made him and Dean the first (and hopefully the last) stallions to wear them, and Dean’s fragile masculinity was only slightly assuaged by the other lore Sam had dug up: that when used together and at full power, the Elements could produce a magical force the likes of which could level a mountain, or maybe even, if they were lucky, kill an archalicorn.
Generosity chose Sam. The enchantments on the necklace made it fit him, and now the metal clamped firmly around his throat. Castiel had been the only one not to react when Kindness snapped shut around his neck. The rest of them jumped or gasped at the pinch. Sam couldn’t forget it was there once it was on, not for a moment. He’d been sure that they wouldn’t come off until they were used.
He wishes he’d been right.
Now, Loyalty sits heavily in his saddlebags, grating against his own magic with every step. Dean had gotten his wish, and now he carries Honesty and all that was left of Jo with it. And Kindness? Gone with Castiel the minute they got there. So, yeah. They’re fucked. The clinging metal of Generosity traps a lump in Sam’s throat as he tries not to think about what this has already cost and how much more they’ll lose before it’s out.
And it will be his fault. For not figuring out how to summon the Element of Magic. For insisting they go through with this insanity in the first place, using the Elements of Harmony to blast Lucifer out of the sky. For being the one to set him free in the first place, despite thousand-year warnings he’d been happy to ignore if it meant killing Lilith with his own magic. For being born at all.
Loyalty crackles angrily, furious to even be near him, much less his to use.
He wonders if Dean feels Honesty snapping at him the same way, setting his feathers on end. Sam can’t tell. Dean’s wings have been tense from the moment they set hoof in this town, ready to flare up in intimidation or fly into a fight he can’t possibly win.
Dean turns back to him before they’re on the last leg of the journey, the moment when they have to split up so that they can make sure Lucifer has no way out of the blast range. This was a plan meant for five people. He and Dean will have to do it with two, and only four Elements between them. For a moment, Laughter glows around Dean’s neck, scattering bright blue shards across his green fur. Dean has always known what to say to make things better (or exactly what to say to twist the knife) and right now, Sam needs his brother to tell him they’re going to win.
Dean doesn’t say anything. The light dies, leaving him and Sam only bathed in the purple glow of Generosity. (It hasn’t faltered since Sam put it on.) Dean takes to the sky, and Sam puts his head down and levitates a shotgun to his side.
Sam walks through a sea of... He doesn’t want to think about it. Corpses or living ponies, all filled with the dark smoke of demons. None of them stop him. They’re paying rapt attention to their God, but they part for Sam, forming an aisle for him to walk up. Sam cocks his gun.
“You wanted to see me?” he yells, and as the last demons wearing ponyflesh move aside, his eyes land on Lucifer and horror sinks in his gut at the sight.
Sam has grown... used to the reality of alicorn possession. With Castiel around, it would be hard not to. Sam is viscerally aware of the fact that Jimmy was only a unicorn like Sam when Castiel possessed him, and that the wings that leave his back are only a manifestation of the alicorn’s magic, an illusion broken when they sweep through solid objects like nothing. Sam has seen other alicorns, too, manifesting horns or wings or both, never solid to the touch but enough to show their power, enough to kill with. He listened when Dean told him about Raphael, and the arcing lightning that left his vessel’s back. That’s almost what he expects to see from Lucifer, who has only appeared to him in his dreams as an earth pony and nothing more.
Lucifer’s wings and horn are not formed of glorious and beautiful magic. Lucifer’s horn is a jagged, broken thing that bursts from his vessel’s skull. His wings have torn free from his back, one folded at his side and the other bent wrong so that it can’t close fully, exposed tendons and muscle visible underneath the brittle feathers. They might have been white, once, as they were in the rare paintings of him before his Fall. They aren’t any longer, so covered in blood and ash and sulfur that Sam can’t see what shade they are. Before Lucifer turns, Sam’s eyes fall to his, or his vessel’s, cutiemark, only to find it completely scarred over with blistering skin. The parts of his coat that aren’t beginning to burn look blue, but his hooves are dirty. When he looks back at Sam, he swings around with a shovel held in his mouth. He sets it down, wings lifting at Sam’s approach, showing off even worse damage on their undersides.
He looks like a festering wound, not a creature of myth.
A horrible part of Sam wants to pity him. He crushes it down.
“Oh, Sam, you...” he trails off. Sam refuses to look at the sky. Dean will descend from above the moment he gives the signal, and Sam won’t give him away. Lucifer trots forward a few steps, but he stops when Sam raises his gun. Lucifer tilts his head. There are burns curling around where his horn erupts, a different shade than his blue coat. Sam notices, sickeningly, that it matches the color of his own horn. The same size, even, or they would be, if the tip of Lucifer’s wasn’t shattered. “That suits you.”
“What?” Sam’s concentration falters, the glow of his levitation spell flickering out. He refocuses harder, but as it has since his detoxing, he can already feel a migraine building at the base of his horn. Even the smallest spell strains him now. Lucifer takes another step forward and tips his head.
“Generosity,” he says. Sam feels a chill run down his spine. His spell threatens to give out again.
Lucifer knows.
“It was mine once,” Lucifer continues, soft and wistful. “Generosity, and Honesty, and... That reminds me.” He turns from Sam back towards the hole he was filling before. Sam prepares to give the signal, bringing the Element of Loyalty out so that Dean knows to begin using his, but then Lucifer’s horn lights up. His magic spirals up his horn until it reaches the broken edges and then it snaps and sparks like a Tesla coil. Sam braces himself, dropping his gun and preparing a shield spell despite the lancing pain in his head. Lucifer doesn’t attack. His magic engulfs something left on the ground and he lifts it up.
It’s the Element of Kindness. Sam’s heart plummets.
“You lost this?” Lucifer asks. Sam lets his desperate fear channel into rage. It’s always been easier that way.
“What in Tartarus did you do to Cas?” Lucifer’s eyes widen for a moment. He mouths that, Cas, like a nickname is something foreign to him. He draws the Element closer to himself, lifting a muddy hoof to nearly touch the gem. It glimmers pink for a moment before fading again.
“I don’t want to hurt any of my brothers,” Lucifer says. “No more than you want to hurt yours.” He levitates the Element halfway down to Sam. “You can have it. This one never listened to me.” Sam waits for him to drop it again. Lucifer doesn’t.
His head is really starting to pound now. At this rate, using the Elements might put him in a coma. Maybe that’d be better for the whole world. He can’t exactly say yes if he’s unconscious. Hesitantly, Sam reaches out his own magic. He skirts the edges of Lucifer’s power. He can feel it, cold and captivating, enough to set Sam’s fur on end without even connecting. He has no choice if he wants the Element, and so he lets his magic slide between the empty spaces of Lucifer’s. It fits too well. Bit by bit, Lucifer releases his hold and lets Sam take more of the necklace until his magic has completely withdrawn itself. Sam feels bereft when he pulls the Element to himself.
It takes him a minute to notice that his headache is gone.
“You know I’d never hurt you either,” Lucifer says. He’s watching as Sam lets Kindness float to his side. It doesn’t fight him as much as Loyalty does, but it refuses to come willingly either. Sam withdraws Loyalty from his saddlebag. Lucifer does nothing to stop him. “Not really,” he insists. He looks disappointed, not afraid. Sam knows, instantly, that this is a bad idea.
He wishes there was some way to tell Dean that.
Instead, his brother descends from on high, avenging and righteous. Laughter flares around his neck, and he holds Honesty between his teeth. Sam hears him say... something, but it’s hard to make out. It wouldn’t be the first time Dean’s final quip has been stomped out by the fact that he has to hold his weapon in his mouth, but that’s never stopped him before. Lucifer turns to him, wings spreading low and defensive. His expression twists when he lays eyes on Dean. It still isn’t fear. It’s recognition and confusion and then, Sam is pouring too much of his magical energy into the uncooperative Elements to see anything.
Light bursts from them all, a rainbow of power that has saved the world countless times before Sam and Dean ever got their hooves on them. It falls on Lucifer like a flood and blinds Sam and Dean both for precious seconds as it destroys any and all evil it finds. There are one or two demons standing too close to the blast radius, and when Sam turns, blinking dark spots out of his eyes, trying to see if they’ve been smote, he instead finds them falling to the ground and wailing, kicking their hooves. Other demons rear up and get away from the cleansing light, looking at their comrades in horror.
For one beautiful moment, Sam thinks it might work.
The false dawn they’ve created grows dark again. A circle forms around them where life has sprung back into the earth, flowers growing around Sam’s hooves. Every one of Sam’s cells is screaming in protest at how much magic that demanded from him, and his horn feels liable to crack if he even tries to cast a foal’s spell. Dean’s wings give out, and he hits the ground hard. He only manages to stumble back to his hooves so quickly because of years of experience getting the shit kicked out of him.
And Lucifer...
Lucifer lies still, mangled wings spread over himself, his head resting peacefully in the grass. It’s another pony’s face. Collateral damage that Sam will have to live with.
He’s still staring at Lucifer’s fallen form when Lucifer’s eyes open again.
Dean hasn’t realized it yet. He’s looking at Sam, making sure he’s okay. There’s a moment shared only between Sam and Lucifer where Sam knows they’ve lost and Lucifer gazes back at him. They have tried to cheat the devil of his due, and they’ve failed.
Dean reads the despair on his face. He rears up next to Lucifer, intending to bring a hoof down on the archalicorn’s head, for all the good that would do. Lucifer’s horn fires off without hesitation, blasting Dean away. Sam shouts for him, but even as his brother crumples to the ground, he knows Dean’s alive. There’s too much control in how Lucifer wields his magic to accidentally kill someone.
“Ow,” Lucifer mutters. He gets back to his hooves. His movements are unsettlingly smooth for someone who just took the brunt of a magical force that should have wiped him out of existence. That’s what the Elements do, that’s their whole purpose. To cleanse evil.
Lucifer doesn’t even look fazed. He shakes out his mane, scratches a hoof in the dirt, and before he looks up at Sam again, he says, “Oh. There you are.”
His horn lights up one last time, and from where he was just lying prone, he lifts up a crown set with a star. Sam knows what it is. He’s looked at it’s picture to many times not to recognize it on sight.
The Element of Magic does exist. Sam even managed to be the one to summon it, in the end. His horn throbs in pain.
“Hello, old friend,” Lucifer says to the stone set in the crown. “Tonight’s meant for reunions, isn’t it? We still have one more to invite to the party.”
It glows to match his magic. Lucifer smiles.
Sam has never felt more helpless in his entire life.
Carefully, Lucifer floats it above his head. He bows to let it rest behind his horn.
It doesn’t fit right. It’s crooked.
Sam has a horrible feeling that it won’t be, not when- If Lucifer ever places it on Sam’s head. Generosity shines brighter around Sam’s throat. Loyalty and Kindness lie forgotten on the ground, Honesty lost when Dean was thrown, and Laughter still clamped and silent around his brother’s throat. And Magic sits on Lucifer’s brow. He sweeps his wings into the air, imitating the many stained glass depictions of alicorns that Sam has seen. He is monstrously regal.
“Now,” he says, as though this was all a minor, buzzing interruption, “where were we?”