Fun one! And very on theme! The power ups are a nice way of rewarding the player for knowing the map, although I feel the game doesn't really require you to use any of them. Also, personally I would have preferred having multiple lives per run (side note: TIL cats don't have nine lives everywhere :D) – sometimes losing can come real quick. The absolute highlight for me was the music, tho. Well done!
On that note: Your volume sliders don't work correctly! With good headphones / boxes you can still hear the mice at the lowest setting. Also I'm pretty sure the steps are linear. However, human volume perception is not! There's a `linear_to_db` method in Godot to work around that fact – look it up!