Low FPS, worsened by bots and the larger area but generally under 15.
I wouldn't say it's CPU side though, I'd recommend running through everything that could be in the physics buffer and disabling it until you notice a larger drop.
(also if it is, 60 HZ seems a bit much, and the effects won't be much different from 30 or 20)
it would help me tremendously if you could tell me your GPU, especially since you also said you don't think it's a CPU issue. i have an office grade laptop with an integrated graphics card, and i get steady 60FPS, so it could well be a GPU/driver quirk or Godot simply choosing the wrong GPU on your system. if you are on windows, there is a %APPDATA%\Godot\app_userdata\Kraft\logs\godot.log file which says what GPU the game selected on startup.
