Empires rise and fall. Wars are lost and won. People are born and die.
And Merlin watches.
He is a watcher now. His heart is on the Isle of Avalon, and it hurts too much to take it out so he leaves it there.
He watches Gwen become Guinevere, the Commoner Queen. He watches the Great Queens, the High Queens, rule over Albion. He watches peace and prosperity reign.
He watches Gaius die.
He watches Percival die.
He watches Guinevere die.
He watches Leon die last of all, because Leon was as close to immortal as any ordinary man could get.
He is not a watcher then. For each of them he becomes Merlin again, just for a few minutes. Just so that he might say goodbye.
And Merlin waits.
He waits while Albion, England, Britain goes through trial after trial, passing through the fire in a hundred baptisms. He waits while tyrants carve out rivers of blood and the world goes to war again and again. He waits as danger and destruction raises its head and is defeated so that it becomes dormant once more.
He does not fight in the wars.
He works as a physician and nurse, healing others through what medicine can do and what medicine can't. He is careful with his magic. He watched as magic died, and he knows that he is the last of his kind. He has seen what people do to one another because they can't handle someone with different colored skin. He can't imagine what they'd do if they knew that magic was real.
He studies a lot. He goes to university again and again in his true form, his young form. He doesn't make friends. He can't bear to watch them die. But he learns a lot about science and history and literature. The science helps him in his study of magic.
He writes his own book.
He never shows it to anyone. Nobody could make sense of the spells in it anyway. But it's nice to have everything in one place, organized and set down on paper.
Gaius would be proud.
Sometimes Merlin fears that the spell will wear off. It was the biggest and most complicated spell he had ever cast. It was made on the thinnest of hopes, cast on the shakiest of knowledge.
Merlin bound his life to Arthur's.
He saved Arthur from death, but Arthur now sleeps, only to wake when it is Albion, England, Britain's hour of greatest need. And until that time, Merlin will not change. He ages only when he wants to, as a temporary spell. He is no older in form than he was on the day he said goodbye to the man he loves.
At first, he is hopeful.
Then, he is despondent.
He reads tales of King Arthur of Camelot and his Knights of the Round Table. It's a fascinating look at how time warps the truth of things.
For instance, Lancelot now has a son named Galahad. The Cup of Life is what Merlin assumes was the inspiration for the Holy Grail Quest. Gwaine is now Morgause's son and has three brothers, one of whom is named Agravaine. Merlin is portrayed as an old man, and it makes him laugh that his disguise worked so well as to permeate the ages. Mordred is the son of Arthur and Morgause, which would make him laugh if it didn't hurt so much. Sir Leon, Elyan and Gaius aren't even in the story, and Guinevere has been made a princess from birth.
There are a lot of changes, enough to make Merlin bitter. But he's bitter enough already. He has too many regrets to count, and he can't afford another one. He should have taken Morgana into his confidence, shown her his magic and told her about her own. Or he should have let her die. He should have trusted Mordred completely, humbly accepted the druid boy's admiration and extended the same to him. Or he should never have rescued him and let him die back when he was a child.
So many choices. So many wrong turns.
He has all but resigned himself to a fate of living forever, and is contemplating journeying to the Isle of Avalon himself and just lying beside his husband's corpse for all eternity, when he hears the news.
"The royal couple have had a baby! It's a boy!"
The king and queen have been trying for years, with no success. There has been talk of the king adopting his stepdaughter so that she can rule if no blood heirs come along. But now, there is nothing but tribulation.
"What's his name?" One bystander asks another.
"Arthur," the second bystander says. "They named him after that one king, of Camelot. His name is Arthur."
The feeling is so foreign that at first Merlin doesn't even know what the strange sensation is, but then he remembers.
It's hope.
He knows that he shouldn't but he can't help himself.
He perfected an invisibility spell years ago (it would have been very helpful back in the Camelot days, but oh well) and getting past the security systems is laughably easy.
He sneaks past the sleeping king (the queen is still in the hospital—she will die the next day) and peeks in on the infant.
He's adorable, and innocent, and Merlin can already see the resemblance.
"Arthur," he whispers.
The baby coos in his sleep.
He watches over Arthur for years. At first he lets Arthur feel his presence, even if the boy can't see him, but then he realizes what a danger that is. It's not right for Arthur to sense him like this. He could be sent to a mental ward, or worse. So Merlin retreats, only returning when Arthur is in such pain that Merlin can't stand to have him feel alone. He makes his presence known, wishing that he could simply hold Arthur like in the old days, in that past life. But his simple act of being there seems to soothe the young prince, and that is enough for now.
And then Arthur's twenty first birthday arrives. And he calls out, "Emrys."
Merlin has no idea how Arthur heard that name, but there is no doubt who he is asking for.
Arthur begs for Emrys to show himself. That he needs Emrys. Please.
Merlin could never refuse Arthur anything.
"Thank you," Arthur says, and Merlin's breath hitches. It's the last thing Arthur ever said to him, and Merlin just barely stops the tears from flowing.
Arthur turns, and at first he simply takes Merlin in. There's something hungry in his gaze—not predatory, exactly. More like a bookworm seeing the New York City Central Library for the first time, or a soldier coming home after war.
Then something changes in Arthur's expression. It's like wonder and hope and astonishment and sadness and euphoria all combined into one confused look and Merlin doesn't even have the time to decipher it because Arthur says his name and launches himself at him, wraps his arms around him and kisses him, and Merlin is lost, lost, lost all over again.
"I missed you," Arthur says, and Merlin's heart cracks and gushes, truly feeling for the first time in centuries.
"I missed you for a thousand years, you clot pole!" Merlin squawks, but he lets Arthur kiss him again, and again, and again.
And again.