There are an enemy "spawner spitter level 10" (the pink one in the screenshot) that spawns more enemies when you kill it. It spawns completely insane amount of enemies, so much that it tanks my fps completely. (running on a really good stationary rig for 3000 dollars so it's not hardware related).
I guess i could lower some value below the default 1 on the spitter spawner, but still feels like it should be nerfed as default. I'm running on difficulty 10 and I also have race manager and running on difficulty "the one" there but i don't think that does anything, but i'm mentioning it anyway. Every once in a while they swarm from their lvl 10 spitter spawner nests and i have to manually shoot 30-40 nukes in their face to restore my fps xD
I mean....i'm asking for it with these mods and these settings, and i can approach 20-25 fps when i'm attacked from all sides by thousands of enemies at the same time, but going around 5 fps is just painful.
Lag deluxe:
https://snipboard.io/XOLcz7.jpg
Overview map of location:
https://snipboard.io/4qJuUW.jpg