Погребённый

The story is about a human(?) who has spent an endless amount of time in prison.
Not in an ordinary prison, but in the most hellish one. It is terrifying not because of some horrors, but because of its monotony.
It gives you a false vision of control; you think you manage everything in it, but that is far from the truth.
All of this is just an illusion of choice...
Will our protagonist be able to get out of it? What awaits him in the future?
And who is he, anyway, our protagonist?

[Translated from Steam]