It was a well-known fact in Camelot that Sir Leon, Knight and unofficial babysitter of the Round Table, was effectively immortal. The first few times, of course, it was a joke- jests made almost entirely by an overly drunk Sir Gwaine.
"Leon's invincible," he'd slurred. "Dragons, the Dorocha, the whole Cup of Life thing- I mean, nothing can kill 'im! Am I right?"
The other intoxicated patrons of the tavern cheered loudly and sloshed beer out of their mugs.
"I'm not sure that's quite true," Leon said uncomfortably, having designated himself that night as Gwaine's "make sure he doesn't get into a fight he can't handle" friend, since Merlin was working late hunting a rat that had dug itself a hidey-hole in Arthur's room.
Gwaine slapped him on the back. "Don't be modest," he said. "Let me tell you, folks," he said, raising his voice to be heard, "this guy has even survived one of the Princess' Morgana Moods, and came out without a scratch on 'im!"
The occupants of the tavern gasped in awe. The only one who'd ever lasted one of Arthur's foul Morgana-rage-induced moods was Merlin, and nearly everyone thought he was just too blockheaded to notice Arthur was in a bad mood at all.
Gwaine nodded to himself proudly. "Leon's immortal, my friends," he'd stated before promptly passing out at the bar and falling off his stool, leaving an embarrassed Leon to drag him home.
After that, Gwaine referenced Leon's immortality every few minutes until finally, all of Camelot was in on the joke. The latest impossibility he'd survived was a commonplace discussion among the town gossips. "Looks like Leon escaped from Morgana three times the past month." "Oh, fah! Merlin's done more than that in the past week. Not like it's difficult."
Then Leon fell off the tower, and the claims of immortality grew even further with the new proof. Allergy season was always a danger in Camelot, and Merlin always seemed to have it particularly bad, so it wasn't much of a shock when Merlin sneezed exceptionally loudly as the knights were making their way back from training. However, the fact that the sneeze was powerful enough to blow Leon back five meters and knock him off the edge of the tower was.
"Oh, Lord!" Elyan said, turning pale and rushing over to the edge, peering anxiously down at Leon. "Is he- dead?"
"Looks like it," Percival said quietly, staring at the pool of red gathering around Leon's head. "That's blood, isn't it?"
Gwaine glanced down, noticing a disturbing absence from the items he hung on his belt. "Nope," he announced sadly. "That was my wineskin."
"I'm alright!" Leon called up, rubbing his head and wincing. "Just a little bruised and dented."
"Oh, thank goodness," Merlin breathed. A brief thought flickered through his mind- how could Leon survive that fall?- but he brushed it aside, instead choosing to follow the other knights down the tower and congratulate Leon on yet another narrow escape from the jaws of death (and, of course, himself for his continued existence, despite there being very obvious evidence of his being a warlock.)
The next few years passed relatively quietly, at least for Camelot. No more dragon attacks, no more Dorocha, only a few possessions and the like- it was almost a vacation, claimed Gwaine. Morgana, unfortunately, remained as evil and traitorous as ever, but at least no more fallen knights were being raised from the dead and acting very thoroughly out of their normal behavior. Hopefully, all of Camelot prayed, that was a one-time incident. Merlin, especially, wasn't sure he could deal with a repeat.
Then, as all seems to after extended periods in Camelot, things began to go south. Elyan died, and Gwen was enchanted to betray Arthur (again). Mordred's girlfriend turned out to be a druid who'd turned traitor for Morgana, and was executed. Mordred swore vengeance on Arthur for killing her, and betrayed Merlin to Morgana. The Battle of Camlann was the final nail in the coffin. Gwaine was tortured to death by Morgana for information; Arthur was killed by a sword forged in a dragon's breath; Merlin killed Morgana with Excalibur as she gloated over her victory, and somehow, Leon still survived it all.
Peace was brought to the land- a hard-fought, hard-won peace, and one that felt somewhat bittersweet to the Round Table members who remained. Still, Morgana was gone, and the Purge was ended, and finally, finally magic could live in harmony with those who had none. And if Percival talked even less, and Gwen's eyes were always deadened, and Merlin never seemed to smile anymore, and Leon always looked to his left for a king who wasn't there- well, no one ever mentioned it.
From then on, Leon's narrow misses with death became fewer and fewer, until he only had one a few times a year or so. Life was much less dangerous, now, and a little boring, but at least the squabbling old hens who tried to bet on which way he'd almost go next weren't getting quite so much entertainment. Gwen was the first to go grey, and her silver hair did nothing to her well-maintained image as a powerful ruler and brilliant diplomat. Percival was next, and picked up a few more wrinkles around his eyes and mouth, until he was only able to lift one cow at a time instead of his usual three. Then came Merlin, who gained a few white hairs here and there and a scruffy grey beard, though Leon had spotted one of his magic books open to a page on aging spells, so he wasn't completely sure that Merlin's aging was entirely natural.
And as for Leon? Well, Leon grew older with the rest of them, at least in years and wisdom, but old age never seemed to take. At sixty, Leon still looked the same as he had at thirty, and Gwen liked to joke that he was only getting younger by the day. At eighty, Leon decided enough was enough, and called an emergency Round Table meeting with Gwen, Percival, and Merlin, who had officially given up trying to look old and joined Leon in the land of youth.
"Here's the thing," Leon said, leaning forward and propping his elbows on the circular wooden table- the original Round Table- that filled up the small space. "I haven't gotten any older in the last fifty years."
"Really," Gwen said dryly, her hands folded together in her lap. "We hadn't noticed. Elbows off the table, dear."
"Thanks, Your Majesty," Leon said, removing his elbows. "I appreciate your concern."
It was considerably less respectful than Leon would have been in his early years, but he was eighty years old, for gods' sake, and he'd known Gwen since she was barely toddling. He didn't really care about propriety when it was just the four of them, anyway.
"Merlin hasn't aged either, you know," Gwen pointed out, her eyebrows scrunching together slightly under her soft white curls.
"He's Emrys," Leon said. "His name means 'immortal' in the most literal way possible. I think he's kind of a special case."
"He's got a point," Merlin said, folding his arms behind his head and tilting his chair backwards, yelping as it toppled and knocked him onto the ground.
"True," Gwen acknowledged, raising an eyebrow at Merlin. "He certainly still acts like a child."
"Hey," Merlin protested weakly. "And anyway, Leon's got his own magic."
Leon choked on a swallow of air. "What? You know I haven't got a lick of magic!"
"Well, yeah," said Merlin, waving a hand helplessly, "but stuff just sort of…bends around you. Magic, pointy objects, time, Cook's apple dumplings- anything potentially fatal or dangerous."
Leon sat in shock for a few minutes. It wasn't the strangest thing he'd ever heard, but normally the truly odd things only happened to Merlin. He supposed continued exposure had caused him to get secondhand weirdness. "How on earth did that happen?" he finally managed.
Percival, who up until that point had been absolutely silent, shifted on his hard wooden chair and laughed under his breath. He'd gone a bit…senile, perhaps, in his old age, but could still be relied upon for an occasional wise word, or else just as entertainment. "Maybe Fate got drunk and confused you for Merlin," he suggested.
Personally, Leon felt that was a little unlikely, but as centuries passed and he still didn't die, he realized he didn't really have a better explanation for his continued existence in the mortal world. By the time he actually accepted that as reasoning, Camelot had fallen and everyone he'd ever known, save for Merlin, had long since passed. Still, he thought, things could have been worse than having the most powerful warlock who would ever live as your roommate/travel buddy/frat brother.
After all, he'd been to nearly every corner of the seven continents, stopped Merlin from getting a pet elephant as a familiar ("You already have a perfectly nice owl, Merlin. Besides, Archimedes might get jealous"), and was there for the invention of peanut butter toast. Besides, it was only until Arthur was reborn.
At least things would never be boring, Leon thought wryly as he watched Merlin swearing in Old English as he tried to explain to a young lady in the Home Depot that he wasn't insulting her, he would just like to purchase a hoe, and did she know where he could find them, and "Dear gods, I'm sorry, get-that-thing-from-my-head!"
Modern English was confusing.