Your game was really fun. A really solid core mechanic and it feels good to micromanage the machinery and your movement. The spritework is great, and the atmosphere with the music is really nice. This feels like it could be expanded to a full game.
However there are 4 things that kinda bothered me:
1- The hallways feel too narrow. It's not unusual that when you're cornered and manage to stun a bunch of them, they inmediately get replaced. And the un-ghost/re-ghost animation is too long to multi dash forward.
2- More than once my ghost got stuck in wall edges, killing what I felt were promising runs. Does it use move_and_collide instead of move_and_slide?
3- Killing enemies does nothing: I know that vanishing the common guys is supposed to clear the lanes but at some point they come in larger groups that my mouse can drag. If in the future you manage to make them more distinct by giving them different movement patterns or speed that could really spice up the gameplay.
4- No healing: Since every mistake is permanent in a run, if you make one early on, you're compelled to reset manually. Which can be a pain point on some users.
These don't change the fact that you have something that is already good with even more potential in here!