You can't Troll Headmistress Fiora. You just can't.

If you going as the Troll King (Trundle), you better throw that E - Pillar of Ice on her right after she goes in to proc passive. Then Q W. Better do it quick though. A smart Fiora will parry your Q.

She parried my Q, Ignite, and Ult. She got a Pentakill later on. Now I am traumatized and cant sleep unless I run it down mid.