Game frame rate near 0 (x1)

For some reason this last update (haven’t played since bloody harvest) makes my game’s frame rate drop and/or freeze pretty much every 5-10s for about 1 or 2s depending on how many enemies there are and abilities I have active.
Zane currently makes it the worse rate drop with clone and sentry.

What happened? the game is almost unplayable since I can’t aim during the drop/freeze. Heck even when there are no enemies it can STILL FREEZE while running about.
it used to run fine. what happened?