Hybrid Widow meanest spider ever? (Overgrown Ruin)

In this otherwise low level map I was one-shot twice by this mean, mean spider.
Actually everyone else was also killed except the leader because he ran past it, but they quit out.
I was not hit by the chaos, it was one shot flicker kill.
Does anyone know what kind of damage that strike does?
My FP shadow armor in MF gear isn't great and 3500 life and ES not best I realize but as I was not alone I gotta think this beast is uh, avoided by many.

You probably had a %increased monster dmg mod or %boss attacks faster and does 30% more dmg. She does quite alot of dmg, staying close to her and using skelly totems help.