Essence monster bug - monsters aggro before activating essence monster

Ran across another bug tonight.

I started Valley of the Titans and an Essence mob spawned near my start point. As soon as I walked near the mob (without activating the essence mob), they started glitching/aggro-ing where they were able to attack me and chip away some of my health if I stand close enough to them, but they appeared to be stuck in place and just repeatedly quickly "glitched" with walking noises,etc and they just flicker in place at their spawn point.

Some of the monsters also appear to follow me when I leave the essence mob, but I am not able to attack them. I also take damage if I stand very close to the monsters where they are glitching in place.

I'm literally just standing at this mob right now without activating the main essence boss and they are just continually glitching at their spawn points.

Seems like the essence mob activated before I actually clicked on the main enemy to activate the mob.

I've had this happen a few times. they can actually hit you