I think I got soft-locked by the game?
In the second level, I went to the bottom ghost part, went all the way to the right, and then went back up to the non-ghost part there. Then I followed the top path towards the left, and now I'm stuck in a section of cave where I can't jump high enough to exit it from the right part, nor high enough to exit it from the left side. There are no lanterns in here. If it's unclear what part I mean, all I can tell is what I still have on the screen, which is when I'm on the left part of the cave I'm stuck in, 4 ghosts are visible below me, when I'm on the right part 3 of those 4 are visible below me and a lantern and its mirror on the far right of the screen.
I also think the game doesn't explain its mechanics very well:
It showed how to wall-jump, but I was wondering why wall jump sometimes works sometimes not. Only later it was clear that that's because there was a lantern. The point in level 1 that shows the wall jump does not make clear this is only possible with the lantern.
Then there are those ghosts which have a lantern that pops up when you try to walk to them to press F that don't work unlike the other ghosts. So apparently those only work after you activated all lanterns, which was also unexplained and unclear since now it seemed as if the lantern's function was just to help you jump.
The atmosphere and graphics are nice though!