The Last Cosmonaut

The Last Cosmonaut is a first person survival horror puzzle game set in an abandoned lunar outpost. Collect parts, repair the escape vehicle, and keep the lights on, as something lurks in the shadows...

At a glance

• Platform: Windows, macOS, Linux.
• Genres: Action, Adventure.
• Release date: Aug 28, 2026.
• Delivered as a Steam library entitlement — activation is handled by Steam.

The developer has not published system requirements for this title 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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