In hindsight, Arthur thinks, the attack was actually fairly clever. A quiet, peaceful night after a hunt, a Mercian boy with a mind for vengeance after Arthur claimed the life of his father in battle, and a single arrow from atop a tree free of wind and clear of distraction; one arrow, just the one, and the knight on watch wasn't even asleep or otherwise preoccupied. It was simply that easy, and everything passed in a blur of silence.
The sound of the boy's bow being released, Merlin's body climbing on top of Arthur's, and Sir Leon firing a single bolt from his crossbow, all at once. Deadly silent. Arthur even took a moment to mentally remark on his knight's ever flawless marksmanship, and would have reached over to clap him on the arm if not for his servant's weight holding him down.
If not for the wooden flank in the center of his servant's chest.
It takes a moment longer for the sight to register, for the events of but a few seconds to click together and form anything coherent - it takes that moment for Merlin to cough, and something red to spill from his lips. Arthur's brows furrow, as though he can't for the life of him fathom why there should be anything red on Merlin other than that stupid neckerchief, and a hand touches his cheek. A cold hand. Merlin's hand.
"Hey," he says in a voice that is not his own, can't be because Merlin's voice is singsongy and childish and this sounds laboured and wet and ugly. "Hey, Arthur. Arthur. Arthur, hey," and Merlin's rambling, near frantic and pawing at Arthur's shirt weakly. Merlin's smiling - grimacing, "Don't - Arthur, don't pull it free, huh? Don't take it out. It'll - it compliments my eyes, hey? Don't take it out, Arthur, don't -"
Arthur takes it out. Merlin screams. No one dares to call him a girl for it, even when the screaming stops and Merlin's slipped into unconsciousness.
The Prince refuses to wait until the cover of nightfall recedes, and arrives in the courtyard by midsun despite being a day's ride away, yet the world is no more brighter for it because Merlin has still not woken. Arthur is faint from shouting commands to the guards and stablehand and explaining to Gaius and his father, and all throughout, Merlin does not so much as open an eye. Every bit as lazy as ever; Arthur says nothing of it.
By the time he is relieved from the King's presence (ordered away, shouted away because that was reckless and foolish and 'He's just a serving boy, Arthur,' and no, he's not, he isn't, he never was), Arthur enters Gaius' chambers to find the physician and Guinevere crowded beside the cot where Arthur sat when he broke his leg falling from a horse when he was seven, where Morgana refused to cry from the cut across her hand when she stole Arthur's sword to practise, where Merlin is laying and breathing and dying and Arthur might order the cot burned behind the castle later on.
Guinevere's eyes are red and her cheeks still wet when she rises to bow her head; Arthur wants to brush her sadness away, to embrace her and remind her Merlin is too stubborn to die. He nods his head to her and turns to Gaius. Time has not been kind to the man, but Arthur swears he ages another decade in the time it takes to say 'There's nothing more to be done.' Arthur nods his head again and pulls up a chair beside the cot, prepared to take his father's wrath for however long he spends wasting time at a servant's bedside.
It takes only the day.
"Arthur," and the Prince nearly jumps right of his skin, ready to shake Merlin for scaring him so much, to praise Gaius and yet another of his astounding remedies, to do anything but breathe when he realises Merlin hasn't woken, but is speaking in his fitful sleep. "Arthur," he croaks, eyes still closed, clenched with a pain Arthur has known and seen and watched greater men fall victim to. "I'm sorry. Arthur, I'm sorry, I'm sor - Arthur."
The customary shut up, Merlin rests at the tip of Arthur's tongue, but all he says is 'please,' and for once, Merlin listens. He stops his feverish mumbling.
And then he stops breathing.
And then his heart stops beating.
Arthur won't let himself cry, because he will be King one day and Merlin is not the first and will not be the last man to lay down his life for him. He won't let himself cry, because that would presume something tragic about Merlin's life, and there is nothing of the sort in his blatant disregard for station or his absurdly inane insults or the way his eyes crinkled when he laughed enough to light up the sky. He won't let himself cry because a hand touches his cheek. A warm hand. Merlin's hand.
Arthur thinks he must be magic.
He doesn't care.
Merlin's voice doesn't waver, and this time, when he smiles, Arthur returns it in kind. And then he calls him an idiot.