Sirius halted long enough to allow the cloak to inspect his wand and then cast a series of different diagnostic charms: many of them non-verbal, but a few of them he muttered underneath his breath. He tossed in a mild soothing charm while he was at it and then stood back up.
"Speaking colloquially, I'd say he's tuckered himself out, magically and emotionally," Sirius said and tapped his wand against the palm of his hand, considering what to do next. "He needs rest. The fastest I can brew a Dreamless Sleep Potion without it losing its potency is around thirty-three minutes. I can administer that while he's still out, and he'll wake up when he's ready."
He glanced over at the cloak. As far as Sirius was concerned, the cloak was the closest thing Strange had to a next of kin right then. "That's option one. Option two, I blend it with a Draught of the Living Dead, so he stays in a dreamless slumber indefinitely, or until he's given the antidote, which I could administer when whatever this bullshit is over with. Option three, I do option one, then offer him option two when he's woken up. What's it going to be?"