Indie Game Spotlight: Vapour
This is a bit scary, but more just pain-in-the-ass hard. Floating around a foggy landscape trying to dodge enemies that are way too fast while collecting six pages. Or some amount of orbs. Whatever, you collect thing and the game doesn't make it east.
It's worth the challenge, so if you want you can grab it here: http://www.skobbejakgames.com/