At first I didn’t get how the game was supposed to work since there’s a lack of instructions. It seems there’s some in-game tutorial with the sign but I didn’t know what buttons to press to interact with it. After trying out the keys on my keyboard I found out you’re supposed to press Ctrl to switch to “spirit” mode.
The camera being stuck to the player makes it feel bad to play the game, I’m sorry to say. It’s very jarring when you jump and even more so when it’s suddenly switch place with the spirit mode. You can’t see ahead of the levels so you don’t know what you’re supposed to do. In the second level, where there’s a section of invisible platforms and you basically have to jump blind, the background not moving gives not indication of where you are in the game space so you can’t adjust your jumping mid-air.