Disclaimer: I don't own Merlin also could be seen as possible spoilers for the series finale
Destiny wasn't always bliss, in fact sometimes it could be cruel. For Merlin and Arthur, it was pure hell.
So Kilgharrah and everyone else got it wrong, well sort of. Merlin was Emrys and Arthur was the Once and Future King but the two were stuck in a cruel cycle. The first thousand years after Arthur's death, Merlin roamed the world alone waiting for the day he would return but nothing was ever simple. Not for Merlin and Arthur.
Merlin felt it, his magic waking him up at a mere four in the morning. He had never felt this way before. His magic stirred within him, pulling him to the place just outside his simple home. The Lake of Avalon.
He lived in a small cottage just on the shores it was all he needed and nothing more. Merlin kept himself sane over the years by writing Arthur letters, there were so many. One for every month he had been gone, it transformed into more of a journal then letters, but they kept him grounded. He never expected Arthur to need them.
This was it Merlin thought standing on the shores, the lake lighting up a magnificent, shimmering gold, it was just becoming dawn, the sky was a mix of orange and pink as the stars faded in the light.
When he emerged it was blinding, the sun reflected off his armour, but that didn't matter. Not to Merlin. He ran straight into the lake, holding back tears as he went.
Arthurs grin matched the sun when he caught sight of Merlin running towards him. He made his way forward as fast as he could towards his former manservant.
It was finally here, thousands of years in the making, destiny finally being complete, but nothing was fair, not for Merlin and Arthur. Just as the two were about to meet, their hands inches apart, Merlin's body jerked forward slightly and a tiny blood spot appeared on his chest and the blood flowed and flowed. Arthur's ears finally caught up with what he was seeing. The sound was indescribable to Arthur, all he knew was that it was as loud as an explosion and now Merlin was bleeding.
Before Arthur could say a word or before the two could even touch Merlin fell forwards into Arthur's chest. Dead.
The cycle never stopped, the two wouldn't even get to say anything before the other was dead, they were only able to just make eye contact before the other was alone.
Destiny wasn't always fair, not to Merlin and Arthur.