So basically i had an MF, that to put it nicely, was stupid and thought that Deathfire Touch worked on MF's Passive.
So i am here (kinda to stop me from tilting completely.) to try and clear something up.
Deathfire Touch does not activate on things considered an Auto Attack (Ezreal Q, MF Q and the like).
Deathfire Touch doesn't activate on many passives.
Deathfire Touch if it does work gives a visual indicator, and deals magic damage over time.