Project: Mortuus Astrum Playable Teaser

A first-person cosmic horror short experience set in a hallway-style map, where you uncover the secrets of an abandoned facility while being stalked by a mysterious entity

At a glance

• Platform: Windows.
• Genres: Action, Free To Play.
• Release date: Oct 8, 2025.
• Steam user reviews: 4 user reviews (100% 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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