Dark Matter Planet

Dark Matter Planet is a side-scrolling action game with a horror atmosphere. It was created as an entry for the 2008 TIGSource Commonplace Book competition, and was inspired by the following entry from H. P. Lovecraft's notebook:

Planets form’d of invisible matter.

The player controls an explorer on a planet where everything, including the terrain, is invisible. The only way to figure out the terrain's shape is throwing pellets, of which the player has an unlimited amount. The terrain contains obstacles such as blocks to push, quicksand, and invisible enemies. These enemies can be avoided, or killed with a gun, although there's only four shots available for the entire game.