The changing of a destiny starts like this;
The King and his knights and Merlin are on a routine investigation into a lead on Morgana. The castle they are pointed to is old and weathered and as much a ruin as her previous hideaways. There is no sign of her being there currently, but there are signs of previous occupation and quick clearance. They split up, and Merlin finds himself in the group with the newer knights. With Mordred.
Arthur sent him off with a pointed stare and Gwaine made a crack about keeping the duckling in line. Mordred took the lead and Merlin followed at the back. Everything seemed normal until the third corridor. A loose stone sent one of the knights stumbling into a wall and started a chain reaction of events, beginning with the crumbling of the wall and ending with Merlin and Mordred trapped in a side room in the floor below.
What starts as an argument about using magic to escape escalates, as many of the interactions between the two so often do, into an argument about what Mordred truly wants in Camelot.
And this is how a destiny begins to change.
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"All I have wanted was to be considered your equal! To be considered worth your time!" The scream is torn from Mordred's throat and Merlin's blood runs cold. The words are ones he is painfully familiar with, though he has never said them explicitly. And yet he is already laughing, even as he takes note of the wet shine to the druid's eyes.
"How can we ever be equal when you seek the death of the King I live to serve? You will never be my equal by any means. The only time I spend on you will be to stop your inevitable betrayal." His words are harsh, biting in their attempt to force Mordred to anger. Anger is easier to deal with than what Mordred is threatening to unleash. Anger would give him cause to scowl and glare and glower from afar for the next week or so. But the druid does the opposite of what Merlin wants, as he is prone to do these days.
Mordred flinches against the stone wall, as if Merlin had physically hit him. His expression is raw, open in a way it hasn't been since he entered Camelot's walls and was deemed a knight. He seems to struggle for breath for a few moments, eyes fixed on Merlin's. Guilt pools in the warlock's gut, but he forces himself to ignore the acidic sting. He could not pity the man who would one day bring Arthur to his knees on the battlefield.
"All I have-," Mordred's voice breaks and he hiccups a laugh; an ugly, painful noise that makes Merlin want to look away, "All I have done was to get you to notice me. I came to Camelot for you, Emrys. Not for Arthur or some foretold future or for a destiny I don't want!"
And Merlin can hear the truth in the scream, even as Mordred's magic flares up, slamming him into the wall. He pushes back and breaks the hold easily, and Mordred laughs that painful laugh again, sliding to the floor like the fight has simply drained from him. Merlin watches, emotions and reason and logic and fact warring inside him in a battle to be the dominant driving force of his actions.
Silence falls for the moment, and Merlin watches with an almost detached horror as tears fall from Mordred's eyes.
"I grew up on stories of you, Emrys. Tales of the mighty warlock who would return magic to the lands once more." The silence is broken by Mordred's quiet words. The heels of his palms are pressed over his eyes, though the tear tracks linger on his pale cheeks. "And then I met you, and you were more than I could have hoped for; more than I dreamed of. And you let me live. Where others would have killed me. You let me live." Mordred trails off, shaking slightly. Shame curls next to the guilt in Merlin's stomach.
"You were a child." Even as the words leave his lips they taste like ash. Like an excuse he barely means. Mordred doesn't react for a moment and then,
"So you will save the child yet condemn the man." It's not a question. The statement seems hollow, and Merlin swallows thickly, revisiting the vision again. He sees the battlefield and the final blow. The cruel smirk on Mordred's lips and the dead stare in his eyes.
He feels sick.
"I don't know what I'm doing." He laughs as he says it, sliding down the wall until he's seated on the ground like Mordred. They feel like the most honest words he's spoken in a long time and he doesn't know where they came from. He's just so tired.
The past years of his life have been one destiny fuelled action after another, to keep Arthur safe, keep Camelot standing, keep Morgana at bay, keep Arthur from knowing the truth, keep Arthur's view on magic as neutral as possible, keep Arthur's enemies at bay, keep Arthur from becoming cruel and jaded. Arthur. Arthur. Arthur.
And Merlin loves him. Loves him like a brother, like a vital part of his own being, loves him almost like he loves his magic. But there is only so far love will go to keep oneself sane. There are times when all that Merlin wants is to scream until he is hoarse that he has magic. When Merlin wants to tell Arthur the truth, tell Camelot the truth and have it be known that magic can save people. Has saved people.
But each time he thinks he might be able to Morgana appears with a new scheme, or a mercenary group attack outlying villagers using magic to help. And he can't. He can't tell Arthur of his magic after such ill fortunes.
There's a smile on his lips now, but it feels wrong, twisted somehow. He can't bring himself to care. Mordred's eyes are still hidden and Merlin watches a spot on the wall above his right shoulder. If he doesn't think too hard he can pretend he's talking to himself, as if Mordred isn't in the room to hear his darkest secrets.
"Kilgharrah wanted me to kill you. Wants me to kill you. Destiny. Fate. Wanted you dead several times over." Broken sentences are the best he can do. He's never given voice to these words before, has kept them locked away in the far corners of his mind. Mordred is frozen now, the shaking stopped. "I said no. That you could change. Would change. With second chances. I didn't like the sound of destiny. Or Fate. Fought them. For too long I suppose. Arthur was my destiny. Is my destiny. And you are his doom. And he shall be his downfall. Whichever happens first. Destiny doesn't care much."
"Why?" It's a barely spoken word, breathed out on an exhale. It could be questioning any of his previous words but Merlin doesn't ask for elaboration. He saw when Mordred's shoulders tensed.
"Destiny. Vision from seers who meddle. Who die. Are dead. You kill him. Arthur. And I can't stop it. Kilgharrah says I should have killed you. But you were a child. Small. Young. I remember my mother used to make excuses, fanciful and believable both when I was that old. Merlin has too much energy. Merlin's got an eye for decoration, the plate didn't match. All to stop people recognizing my magic. But you were young and secure and I. I wanted you to have that security. Knowing your magic was known and wouldn't be betrayed."
Merlin pauses. His thoughts wander for a moment before returning with startling clarity.
"Destiny became everything I suppose. Make sure Arthur can fulfil his. Make sure Arthur lives to fulfil his. Make sure Arthur, Arthur, Arthur." A bitter edge has crept into his voce so he stops, breathing deep and looking to Mordred once more. The druid watches him openly, eyes wide. He swallows once, twice before he can speak.
"Why are you telling me this?" Merlin shrugs, watching the way light from a shuttered window plays against Mordred's hair.
"I'm tired of destiny."
They're found nearly an hour later, the trail a dead end. The journey back is filled with good natured ribbing from the other knights about getting trapped in a side room, and for the first time since Mordred's arrival in Camelot Merlin laughed along with the teasing in his presence.
(())
After that things… changed.
Not in a drastically noticeable way at least. The tension that used to grip Merlin's shoulders whenever Mordred was near fades, but since no-one had noticed the tension before it was simply dismissed as Merlin finally warming to the youngest knight. The tension didn't leave the warlock however; it simply found a new target.
Now there was a hesitance around Arthur. And sometimes, during meetings when everyone was beginning to get foggy and distracted by the grooves on the table, Mordred would glance at Merlin and the warlock would be watching Arthur. Except it wasn't the same as before. There was an edge to it that worried Mordred. And from what the druid had overheard during training breaks he wasn't the only knight to pick up on the change.