Underplayed Gems

15th Prison (2025)

15th Prison cover
Developer
Zettanium
Platforms
Windows
Genres
Action, Adventure, Indie, Simulation
Rating
4.7 of 5, 33 player ratings
Typical playtime
about 59 minutes
Where to get it
Steam
The 3D catalog: game boxes on wooden shelves, with the cat sitting at the counter next to its greeting.

The catalog in 3D

The same catalog has a room you can walk around in. The cat behind the counter is the AI Catbot, and they pick real games from it when you tell them what you feel like playing. Nothing is for sale, here or in there. Go in from here and this game is already out on the counter, with more like it waiting on the shelf next to it.

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How it feels

You methodically explore a grim prison, collecting envelopes and solving puzzles under a looming sense of dread.

atmospherictensepacingexplorationpuzzle-filledhorrormysteriousprocedural

What players say

Players describe this as a tense anomaly-spotting game set in a prison, harder than many in the genre. It is short, around two hours, with a final puzzle and some jumpscares. Movement feels a bit janky, and the game is very quiet. Reviews agree it is addictive and frustrating.

Screenshots

15th Prison screenshot 115th Prison screenshot 215th Prison screenshot 315th Prison screenshot 415th Prison screenshot 515th Prison screenshot 6

More games like this

This page is from Underplayed Gems, a catalog of older and overlooked games. Not quite it? You can browse by platform and genre, or take this one into the 3D catalog and ask the Catbot for something closer.