Update from desktop version : By the time I reached 400k score there was no lag whatsoever
It's isolated to the browser version, I will playtest it in Chrome instead of Opera to see if it's just opera
Chrome : By 450k score there is noticeable lag even without slimes or any monsters on the ground.
With a dozen of any mob the fps drops as well.
Spawning slimes from one end of the map to the other also makes it way way worse.
Chest/Upgrade selection screen lags a bit, but not much. Even with a map full of slimes