Penumbra

Penumbra is a survival horror video game played by Markiplier.

Game information
An ever-expanding world hides behind an underground obelisk. Few know its secrets, however you're not the first. Make your way through several puzzles using the notes left behind. Be careful not to disturb the guardian of the dark wood and the spirit who lives in the labyrinth. You are never trapped as long as you keep moving.

Episode

 * 3 SCARY GAMES #18