idk why I didn't think of this before, but! Merlin's had one of those rabbit-bird things following him around/kind of a pet but he'd never admit it since pretty much the start of the game. It's part running gag and part ICly he sees potential use as a familiar if/when he can use powers again. Since pets CAN be in the dream too, and powers are active, if Merlin were to take advantage of that to get started on the process of making an animal into his familiar, would that work? Or would anything he did in the dream be undone upon waking?