T-posing enemies, very low framerate, crash #1224573472

Bug Report ID: #1224573472

Just entered a map, and we get around 25-40fps when we normally are around 60-140fps. Very stuttery, a lot of enemies start doing T-pose and after they die they're still in a t-pose.
My friend game crashed at the end.

Video recording: https://youtu.be/cec3m0ixMaY

We can provide the 'client' logfile to if GGG staff wants it.

Oh and, visual bug on the amount of minions shown in the top left as you can see in the video.
When switching Item Sets, it doesn't reset to 0 so visually it just goes up and up to the hundreds.