"You forget who I am, Merlin," possibly in more than one way at the look of it, "I can command you to do anything I please and you must obey. That's what being King entitles me too," he speaks slowly, as if talking to a small child. Or Merlin. Who is almost like a small child, even if he's a tad taller than Arthur himself.

"I will ask you one last time, my name, what is it."