At night, Camelot disappeared.
Well, not every night. Not the nights – the hundreds of nights, it felt like – that Merlin was awake, fighting some fresh hell on behalf of the usually oblivious Arthur. And from the perspective of your average guard (nightshift), noble (upset stomach) or townsperson (crying baby), even when Merlin was curled up in bed asleep Camelot remained present. Unsurprisingly, as it was – well – real. And solid. And not easy to conceal in any way.
Nevertheless, from the point of view of possibly the most unique mind in the five kingdoms (and even Arthur would agree with that description), every night that he slept it was as though the Camelot around him did not exist. He would climb the short flight of stairs to his room, weary from chore after chore, and dream of the emptiness.
It wasn't really a valley, just a piece of land that lay slightly lower than the area around it. Sometimes Merlin hung, disembodied in the air, feeling his vanished bones in the wind that whistled through where the castle walls had once been. Sometimes – the worst times, the times that he woke after sweating and shuddering without remembering why – he would be in the earth, turning dry bones in rotted material among a hundred other corpses in the grave of a city. Other times he would walk across the ground, barefoot, dressed as the court sorcerer he'd never been made, left there to mark the place where the greatest stories came from.
No one else ever appeared in this dream with him. Though, in the distance, Merlin could hear a constant swish and rumble and see off shapes moving in endless lines, and he knew somehow that they contained people. But they never came any closer, call to them as he might. It was just Merlin left – everyone else was dead, gone, or oblivious to him. And always, just before he woke, he would realise what it was. It was the future.
And he was helpless in the face of it.