3D horror game. A man stalked for months by the Slender Man has fallen into a deep coma due to Slender sickness. Trapped in is mind, he is taken back to a place dear to him - his childhood home. But he is not alone. Slender Man has followed him. Can you find enough childhood mementos to break out the coma, or will he find you and kill your mind, trapping you in eternal darkness?

Mansion is the fourth map of the Slenderman's Shadow series. It was released on September 8, 2012.

The player is in a large mansion, and the goal is to collect 12 mementos before Slender Man captures the player.

There are two keys to unlock different sectors of the Mansion. If the player can collect 10 or more mementos, a "drunk mode" is unlocked; the playing style is similar to that of Amnesia: The Dark Descent (when the player starts to lose mental health).

In the Unity remake, you don't need keys: the doors are all open at the beginning.