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Arthur thought he had seen the worst of it when an entire camp of druids dropped down on bended knee, heads bowed and hands clasped, and called Merlin Emrys and my lord and the greatest sorcerer ever to walk the earth.
He thought he had seen the worst of it when the quiet, pretty girl wrapped in an old, tattered purple dress crawled out from the silver depths of a magical lake, and told him she was Merlin's wife, except Merlin has never even so much as said her name, because he would probably actually die if he ever had to tell the truth about anything, ever, in his entire life.
Arthur thought he had seen the worst of it when Merlin called up a dragon. When Merlin turned out to be the last dragonlord. When he crashed to the ground, all pale and limp and shaky, in a fit of magical exhaustion. When he turned himself into a girl. When he split himself into nine entire Merlins. When he called up a whole other Merlin from an alternate dimension, and this whole other Merlin turned out to be an absolute lunatic. The little bastard tried to murder Arthur no less than thirteen times because he wanted "justice for sorcerers" or some rubbish like that, before the real Merlin finally got him under control and pushed him back into his world.
(Arthur feels desperately sorry for the Other Arthur in Evil Merlin's dimension.)
Well.
Look.
The point is. This is the point. This is the point right here.
The point is, Arthur thought he had already seen the worst of it, because obviously, it simply can't get worse than Girl Merlin, or Nine Merlins, or Evil Merlin.
But.
That's the thing.
It can.
This is worse than Girl Merlin and Nine Merlins and Evil Merlin, it's so much worse than all of that, and Arthur thinks he would take all of that again before he would take this even once.
"Merlin," he says, and he sounds so wrong, so awkward and off-kilter and not him, and it burns the insides of his ears to hear it, "you have ten minutes to figure this out, and put us right, or I'm tossing you in the pigpen!"
Merlin blinks up at him—and God, this is so weird, it is so weird to see the way his eyes open and shut, the way his mouth opens and shuts, the way his hair falls over his brow, the way his fingers curl and uncurl, clench and unclench, the way his throat jerks when he talks—
"Well," Merlin says, simply, "I already spend all day, every day, with the biggest boar of them all."
Arthur scowls. "It's not funny, Merlin!"
"It wasn't a joke," Merlin says flatly.
"I can't look like this!" Arthur jabs a finger in his own chest. (Is it his own chest? Can he call it that? Can he call it his own chest right now?) "I can't be seen like this, Merlin, look at me! For God's sake! Look at me!" He sweeps a hand down to show off his new and entirely awful body. Except it's not even his body. "I'm you!"
If Merlin wasn't such a colossal idiot, Arthur wouldn't even believe it—the greatest sorcerer ever to walk the earth, the king of the druids and the last dragonlord and the master of life and death and the magnificent, all-powerful warlock Emrys, has messed up with his magic, and gotten himself stuck in Arthur's body.
And he's got Arthur stuck in his.
But.
Merlin is a colossal idiot.
So Arthur believes it.
Merlin scowls. Is that really the way Arthur looks when he's mad? That crease in his brow? That little vein in his neck? "Yes, Sire," Merlin says, acidly, "I can see this is absolutely humiliating for you—"
Arthur shuts him out. He's got bigger things on his mind right now. Like—
"Your ears," he runs his hands down the sides of his head with a little moan. Is this the way Merlin feels? Like he's got dragon wings up there? "I feel like one of Cook's brass pots. With the really big handles. Is that the way you feel? Do you feel like one of Cook's brass pots all the time? Is that why you're so grumpy?"
Merlin glares up from his spellbook. "There's nothing wrong with my ears!"
"There's everything wrong with your ears!" But Arthur takes his hands off his head all the same—it's only going to make him feel worse to think about it, and it's better to not think about it if he's going to be stuck with big ears and an ugly scarf and—
—and—
Oh.
Oh, no.
Arthur rips off Merlin's rough, ratty blue shirt with the ripped-up hem—he can't believe it didn't hit him before, but this is, obviously, the absolute worst thing about being Merlin, and oh, God, it's even more awful than he feared!
"You're so bony!"
"Arthur!" Merlin goes absolutely bright pink. "Put my shirt back on!"
"I—I can see your ribcage! I—I can feel your bones," he presses down on Merlin's narrow, scrawny side, "under your skin! You have no muscle! You look like a girl!"
"Put my shirt back on!" Merlin says again. He's turned all the way red now. "Stop showing me off like that!"
"Showing you off?" Arthur almost laughs. He cannot be serious, can he? "You don't have anything to show off! You're skin and bone!" If only he wasn't stuck with the skin and bone right now. God. He misses his muscles.
"Well, I'm hardly singing from the castle rooftops!" Merlin says, sharply, his cheeks still very red. "I have to look like you!"
Arthur snaps his head up to stare at Merlin. Or does he stare at himself? "What are you on about?" He shakes his head. "You've obviously got the better end of the deal! You get to be me!"
Merlin lets out a very unkind snort. "Get to be you? I feel like a hippopotamus!"
Arthur reels back. A hippopotamus?! "What?!"
"I feel like I'm carrying the Round Table on my arms!" Merlin winces and rolls his—Arthur's?—shoulders. "I'm so heavy!"
Oh. Arthur actually does laugh now. "Yes, that's called strength and muscle, Merlin. Of course, I wouldn't expect you to be familiar with it, but—"
"Look," Merlin says, with a distinct air of utter desperation, "just put my shirt back on, please, and let me focus. I'm never going to find the right spell if you keep whining about this."
"I'm not whining," Arthur huffs, because he's not, kings don't whine, thank you very much, even when kings have absolutely every right in all of Albion to whine. But he does put Merlin's shirt back on—he would be pretty embarrassed of his body, too, if that was all he had to show for himself—and plops down in the nearest chair.
God, it's so strange to look over and see himself in the same way he's seen Merlin a hundred thousand times before—all tucked up on the bottommost stair, spellbook open on his knees, hunched over the dusty old tome with his shoulders up (like a humpbacked old witch, Arthur said, once, and he had bright green hair for a full week before Merlin finally turned him back, honestly, the idiot could be such a girl sometimes—)
"I've got it!" Merlin looks up with a bright grin—even with Arthur's face, he still looks tremendously goofy—and jabs a finger at the page. "Here, it says—oh, it needs a potion, and—um—"
All the color drains from Merlin's face, and he hastily hunches back over the book, almost desperately, and so near his nose nearly touches the thick paper.
"Oh, no."
"What?" Arthur springs from his seat, and rushes over to look at the book for himself, but he already knows he can't read a word of it. "What is it? What's wrong?"
"The—um—" Merlin swallows, hard, and licks his lips, "—the potion needs to steep."
Arthur frowns. Is that all?
"For nine hours."
"What?!"
"The potion itself doesn't look very difficult," Merlin says, thoughtfully, and hunches over the book again. Like a humpbacked old witch.
"Nine hours!" Arthur says numbly. He can't be Merlin for nine hours! He can't! He has so much to do!
"I think we've actually got all the herbs we need in the cupboards," Merlin lifts his head, and looks hopefully 'round Gaius' cluttered, sunlit chambers. "I'm sure I can toss this together before we—"
"Nine hours!"
"Yes, Arthur," Merlin says, and he's got the nerve to sound impatient about it, too. "Nine hours. I thought I already told you that."
"No, no," Arthur shakes his head, so hard Merlin's dark hair tumbles down in his eyes, and he has to reach up and brush it back, "you don't understand, Merlin, I can't be you for nine hours! I don't have nine hours! I have a council meeting in fifteen minutes!"
Merlin finally snaps his stupid mouth shut, but his eyes go wide and round in his—Arthur's—face. "Oh," he says, very feebly. "That's bad."
"And I have three new knights to name in two hours before I have to get down to the grounds for training, and oh, God, Merlin, how am I supposed to spar with my men when I'm skinny as a broomstick?"
"I spar with you all the time," Merlin says. He's gone a bit pink in the cheeks again. "And I'm like that," he waves a hand at Arthur, "all the time."
Arthur snorts. "You do not 'spar' with me, Merlin. You go down with one hit, right off, and you lay in the grass, moaning and whimpering and—"
"You hit too hard!"
"That's the point! I'm supposed to hit too hard, and you're supposed to hit back! You're supposed to pretend I'm an enemy!"
"Yeah, well, it's not so simple for some of us, Arthur, because if I pretended you were an enemy, you would be dead—"
"All right, look," Arthur cuts him off, "we're not going to sort this out if we stand here and quibble about it, so let's get on with it. Go ahead and make the potion, we can leave it to steep in here, no one ever messes with Gaius' things." No one in Camelot has the nerve to mess with Gaius' things. Not even Gwaine. "We can go to the council meeting and explain everything there."
Merlin blinks blankly back at him. "Explain?"
Arthur raises his brows. What's so hard to believe about that? "Yes, Merlin, we're going to explain. We're going to tell the court you mucked up with your magic, again, and it's made me look like you, and it's made you look like me—"
"Um," Merlin says. "No."
Arthur steps back. "No?" His brows lift even higher. "I'm the King, Merlin, you can't tell me—"
"No, Arthur," Merlin says. "Do you want to get yourself tossed in the dungeon? Because that would be the perfect way to get yourself tossed in the dungeon. And burned at the stake at sunrise."
"What?" Honestly, can Merlin even hear himself right now? "They would not throw me in the dungeon! I'm the King!" He stands up a little straighter and throws his shoulders back, but it feels pathetic when he's so scrawny. No wonder Merlin slouches so much.
"Can you prove it?"
"What?" Arthur blinks. "Don't be ridiculous, Merlin, I don't need to prove it, I'm obviously the King, you know I'm the—"
"Yes," Merlin says, firmly, "but can you prove it?"
Arthur reaches, on blind reflex, for his sword, his sigil, his ring, all the things with the Pendragon crest, the Camelot crest, splashed upon them, but—oh—it's all on Merlin now, isn't it, Merlin has his sword and his sigil and his ring and—
—and—
"All they're going to see," Merlin says, "is a servant out to steal the throne."
Arthur tries to scoff. It doesn't come out right. "That's ridiculous," he says, but it's not, and he knows it's not. "No one in the kingdom is more loyal to me than you. No one would ever think you're trying to steal—"
Merlin just looks at him.
Arthur sputters out. He really, really hates it when Merlin's right. It should be illegal for Merlin to be right. He should make that an official law. When he's him again, of course.
(He should also make it an official law that no one is ever allowed to suspect Merlin of treason.)
"All right," he says, finally, "so, what are we supposed to do, then? Just go about our day like everything is normal? Pretend to be each other?" He looks Merlin up and down. "I really don't think you can pull it off. Even when you look like me."
"Shouldn't be hard," Merlin lifts his shoulders in a little shrug. "Walk 'round with my nose in the air, pretend I'm better than everybody, pretend I have literally never seen a woman in my life when Gwen walks into the room—"
"Do you want a day in the stocks? Because you are very close to getting a day in the—"
"You can't put me in the stocks," Merlin waves a hand. "I'm you. If anything, I could put you in the—"
Merlin stops dead. He breaks off, right in the middle, with his hand still up, his blond brow still wrinkled, and he stares, blankly, down at Gaius' overcrowded worktable like he has just glimpsed the very secrets of the universe.
Arthur frowns. He edges a bit nearer. "Merlin?"
"I could put you in the stocks," Merlin whispers, in a voice of absolute and unbridled wonder.
"What?!" No, Arthur does not screech, thank you very much! "No, you can't! Stop talking crazy, Merlin, I'm the King!"
Merlin smiles brilliantly back at him. "Can you prove that?"