Rita's corpse is added to the growing pile of bodies in the banquet room. The Doctor rails and roars and smashes things in the bar for a while. Later, he sits and does his "talk it through till the solution comes" and realizes it's not fear but faith that the creature is after. Howie believed in conspiracies. Joe was a gambler; he believed in luck. "They all believe that there's something guiding them, about to save them," he says. When someone was confronted by their fears, they fell back on their beliefs. He also realizes he's been telling everyone to cling to their beliefs. The reason Rory saw the exit was because, as the Doctor says, he's not religious or superstitious. "There's no faith for you to fall back on." So the Doctor is religious or superstitious but Rory isn't? I'd say Rory has an almost religious faith in Amy, but the episode doesn't have time to deal with his fears. He thinks it was Amy who inadvertently directed the TARDIS to the hotel. "Why?" she asks. "Your faith in me," he says.
He thinks out loud some more and thinks the minotaur is "converting" people's faith into a form of energy he can consume. That's why they start worshiping him. "Praise him," Amy blurts out. They hear the sound of approaching hoofbeats. Amy's about to be turned into a metaphysical salt lick.
Everyone runs and runs through the hotel. The minotaur clomps after them. Amy sees him and she's all, "Oh he's beautiful!" in a low voice like she thinks he's kind of sexy. The Doctor and Rory drag her into the nearest room, where a young Amelia Pond sits at the window with her suitcase, waiting for the Doctor to return. The minotaur is banging at the door. Amy feels her thoughts being changed. The Doctor gives her a reverse pep talk to make her lose her blind faith in him. He knew he would eventually lead her to her death and he did it anyway. "I took you with me because I was vain, because I wanted to be adored." By now, the minotaur has broken through the door and stands there chuffing. Amy looks doubtful. "Look at you, the glorious Pond, the girl who waited for me." He tells young Amelia that they should see each other as they really are. He gives little Amelia a kiss on the forehead and suddenly she's Amy. "Amy Williams," the Doctor says. That chafes me in ways I don't have the time or space to explain.
The minotaur staggers backwards out of the room and collapses in the hallway, panting for breath. The Doctor goes to comfort him, holding his big, rubbery vomit head tenderly in his hands. "I severed the food supply, sacrificing her faith in me," he says. "Gave you the space to die." He pats the minotaur's brow as the hotel dissolves around them, exposing a vast, empty room that looks like the holodeck on Star Trek. The last thing to go is the "Do Not Disturb" sign he'd put up earlier, revealing that this was actually his room and not Amy's.