Devil's Tuning Fork

Devil's Tuning Fork is a game played by Markiplier. It is a puzzle game, where the player moves completely blind. You can use a tuning fork, which will let you briefly see a limited area around you, or where you shoot, like echolocation. The story describes a mysterious disease, which makes children fell into comas, one of them being the player.

Game Information
Devil's Tuning Fork is a first-person exploration/puzzle game in which the player must navigate an unknown world using visual sound waves. Inspired by M.C. Escher’s classic optical illusion and the echolocation of dolphins, The Devil’s Tuning Fork allows the player to explore a new mode of perception through sound visualization.

Plot
As a mysterious epidemic causes children everywhere to fall into comas, one child wakes up in an alternate reality. It is up to this child, the player, to determine the cause of the epidemic and save the other children trapped here. By way of the devil's tuning fork, a magical instrument that allows the player to perceive sound waves, the player must find all the children and successfully escape this alternate reality, thereby waking up from the coma.

Playthrough
Markiplier wasn't able to speak during this episode because while on a airplane trip, his equipment broke, so he spoke over while he was editing the game.

Episode

 * Devil's Tuning Fork