Sleepless

Inspired by "The Russian Sleep Experiment," this co-op multiplayer horror game challenges players to collect crucial evidence from past experiments. Work together to control the gas, evade the roaming monster, and uncover the terrifying truth.

At a glance

• Platform: Windows.
• Genres: Action, Adventure, Indie.
• Release date: Oct 18, 2025.
• Steam user reviews: Mixed (64% positive).
• Delivered as a Steam library entitlement — activation is handled by Steam.

Minimum

Recommended

System requirements as published by the developer on Steam.

Activate on Steam

• Open the offer above — it takes you to this game's official Steam store page.
• Buy it there, or if you bought a key elsewhere, open Steam and choose Games → Activate a Product on Steam.
• Enter the product code exactly as it was issued to you.
• The game appears in your Steam library — download and play.

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