Thank you for such detailed feedback! I agree, that the room without collision was a bad example of a weird room specifically because palyers might think it's a bug. The sanity does take a dive when the player is near an oddity or opens the portal. I was thinking about adding a game over if the player stays insane for too long, but was kinda talked out of it. I think I will add it later.
Inverting the controls is an awesome idea! I think I will add it as a final stage of madness. I will remove the colliders, but I will have to add the spawn places for worms then for each tile. Adding colliders was a fast and easy way to add the worms in the sky and let them fall all over the place, including inside second floor rooms. It was done at the end and I didn't have time to do it any other way. I didn't notice FPS drop, but I must admit, I keep forgetting, that my PC is quite powerful. Thank you for noting this.
The sound was 3D. I guess, there just was someone around constantly, so you didn't notice the difference. It is quite noticable in the headphones, you can hear where it comes from. Perhaps I should have lowered the radius.
Thank you again for everything mentioned! All points are valid and will help me improve the game. I want to use it as my little experimental project to practice polishing and adding juice.