Slenderman Must Die: Sanatorium 2021

Slenderman Must Die: Sanatorium 2021 (Chapter 1) is a Slenderman survival game to find the hidden 8 papers in a scary sanatorium.

Release Date

March 2014 (Android). January 2021 (WebGL).


Poison Games made Slenderman Must Die: Sanatorium 2021.


  • Web browser
  • Android



  • W A S D to walk around
  • Mouse to look around
  • Left Mouse Button to shoot
  • Right Mouse Button to aim
  • Mouse wheel to switch weapons
  • R to reload
  • F to pickup items
  • Left Shift to run
  • Left CTRL to crouch
  • X to prone
  • Space bar to jump

More Games In This Series

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Slenderman Must Die: Dead Space
Slenderman Must Die: Abandoned Graveyard
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