SCP-087-B is a short expiremental indie horror game that was developed by Regalis, who also created SCP - Containment Breach.
The game is a spin-off of the SCP-087 game by Haversine.
In the game you have to walk down approximately 150 floors to reach your objective. There is however several monsters that kill you upon contact, and obsticles down there.
PewDiePie has never completed the game, as it is very rare and difficult to reach the end.
In the ending a Red Mist Monster that you encounter several floors before will trap you in a small rom and kill you. While the game is crashing, A message will appear, these messages are random.