Arthur's biggest fear as of right now is that all of the trials of strife and suffering that he and his loved ones have endured for Camelot's successes will come to nothing, that he will lose everything and everyone for no reason and Camelot will still fall in the end.

His dream will be watching Camelot burn with Morgana dead at his feet, Excalibur in his hand and dripping with her blood ( foreshadowing, anyone? ). He won't actually be falling asleep, though. He will be trapped in option two of the accursed, which means he'll be wandering about his duties half-lucid as he sees his kingdom and his sister dying everywhere he goes.

People that touch him will be able to see the vision in his head, but they'll have to get close enough to him to touch him first. His first instinct upon anyone approaching him is going to be immediate defence-mode. Meaning: he's going to attack. Extreme paranoia and fear and grief and just general despair are going to convince him that everyone is the enemy, and if he already knows them, he's going to think they're the undead come back to claim his life since, yanno, Morgana's kind of done this to him twice now. So good luck with that. :'|b