Strange's smirk just widens as Childermass glares at him. He touched a nerve. Good. He'll have to make certain to touch it again if Childermass decides to remain this stubborn. Still, at the question, Strange nods.

"That will be all. I don't require the plants immediately but don't dawdle in fetching them." No matter what Childermass thinks, Strange isn't an idiot. He knows that it'll most likely take a while for Childermass to find these poisonous plants to begin with, especially in the middle of Portland. And who knows. Maybe in the time it takes Childermass to actually get an assortment of poisonous plants, Strange will figure out just why the hell he wants them in the first place.