What is the skill (big blue diamonds) monsters are killing me with?

Monsters seem to be throwing a totem, trap, or mine that is a big blue diamond and if I don't flee it I'm quickly killed. Not sure if one-shot or just quickly. I'm curious what this skill is because I haven't seen it used before and I'm tempted to use it myself if it is so effective.

The effect is basically a big blue diamond (bigger than my character) that appears next to me and if I move the mob keeps throwing them near me.

Its the summons lightning totem mod on a rare enemy. When you kill the enemy they stop chasing you.

Yes their damage is quite overtuned relative to most things. You just have to constantly be on the move to avoid them.

Thanks.

It has a small delay to start working and by default, damaging area is kind of small. Good luck :)