First of all I don't know why it took about 20 mins to load but maybe it's my internet.
Great concept but here is a thing, The tutorials : I didn't even know what to do at first, I was like is the game really this dark? and then I thought there must be something else to this and I clicked shift (didn't even know it was a thing) and Boom I loved it, so if the mechanic is new you need to tell the player this in-game not in menu (makes it a lot more fun and clear if it's in-game), when I started I knew about movement because it's normal but then a new mechanic, just need to be more clear.
I know this is just a concept and I'm pretty sure you have a lot more cool ideas like this.
Anyway awesome game, keep up the great work :)