I beat Endless 6 for the achievement. Game runs like shit once you get up there, even with all particles off and no damage/health bars. Slogging at 10-15 fps but managed to beat it with like 84min total run time. Used the chaos mage with 4 chaos + 2 shadow spells (golems are op)
Yeah I noticed that too even on Endless 5. My 3080 was chugging and I had everything turned off particles, damage numbers, health bars, etc. Bought me a couple FPS but otherwise you could really tell the performance hit. At one point I thought maybe it was just solely b/c it is trying to calculate all the damage numbers and ticks for 150 different things and 6 skills multicasting every .3 seconds.

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