M.A.S.S. Builder

Commander, customize and build your Mechanical Assault Skeleton Suit (M.A.S.S.) and lead the fight against an alien invasion bent on exterminating the human race. The fate of humanity is in your hands.

At a glance

• Platform: Windows.
• Genres: Action, Indie, RPG, Strategy.
• Release date: Sep 14, 2025.
• Steam user reviews: Very Positive (85% 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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