Someone please correct me if I'm wrong... It is my understanding, from it's description, "Ignite the fires of hate in *an* enemy's heart...", that Inner Fire and it's morphs only aggro/taunt one enemy at a time. If this it the case then I feel this should be changed to allow aggro of multiples within it's given radius. This makes sense due to the fact that undaunted skill line is all about dungeons.
Otherwise, what is it that makes it so special other than you can have it take from the Magicka pool to conserve stamina (just saying). *Adding a battle "roar" when activated would be nice too