Blood Mage Witch, Boss Killer.

https://www.youtube.com/watch?v=U13grsouP00

Showcase of killing bosses really quick on a very unstable, almost full unique gear (2 rare items), build.

I will not post a PoB as I don't like it when people mindlessly follow guide without even understanding them. I think I show you enough things in the video for you to be able to figure out the build and interactions if you're interested.

I have tried running most bosses either with more monster life, enfeeble or life as ES. (forgot to show modifiers every time)