"You're right," Strange can't help but admit, with a frown. After all, it just shot up. That might be impressive for someone who knows nothing about magic, but for Strange it's so dull.

Holding his hands up, Strange mutters something under his breath. And then, in regular voice, he starts to speak. "I am supposed to be a performer, after all. What we need is a bit of showmanship!"

When he said that, Strange thrusts his hands forward, in the direction of Childermass. The flames turn into tendrils of fire, snaking their way across each other, on top of each other, in Childermass's general direction. With the magic, Strange is planning to have it stop just before the fire touches Childermass. However...it's entirely possible that Strange isn't as precise as he's trying to be.