M.A.S.S. Builder
Released Sep 2025
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.
84% positive · 4,126 reviews
Not yet
Released, but content still planned
High confidence
Content Planned
Not yet
Released, but content still planned
High confidence
Content Planned
Where to buy
Green Man Gaming Steam key Lowest $13.99 $24.99 −44% Steam $24.99
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Evaluation
M.A.S.S. Builder graduated from Early Access to its full 1.0 release on September 14, 2025, completing the main campaign story. However, the developers at Vermillion Digital have been very clear that this is not the end of the game's development.
On September 21, 2025, they published a detailed "What's Next" post outlining three concrete areas of upcoming development: a PvP multiplayer mode (a much-requested feature that was nearly ready for 1.0 but held back for further testing), new mech frames (specifically Rex and Spider frames, which are owed to backers as Kickstarter stretch goals), and an expanded photo mode allowing players to pose multiple M.A.S.S. units together. The developers acknowledged they couldn't give a timeline for these features but committed to posting updates at least every two months.
In their October 2025 AMA, when asked how long they plan to work on M.A.S.S. Builder, the developers reiterated that it is a "dream project" they intend to support for as long as financially possible, and confirmed plans for both near-term and longer-term updates beyond the "What's Next" items.
The studio has a demonstrated history of sustained post-launch content delivery — major updates shipped in September 2023 (v0.10.0), November 2024 (v0.12.0), and September 2025 (v1.0.0) — and has been communicating regularly with players. The most recent developer post on record was October 14, 2025, with the AMA answers. Given the developer's stated commitment to bimonthly updates and the specific undelivered promises on record (Kickstarter stretch goal frames, PvP mode), further content updates are clearly planned.
Evidence
AMA answers confirm ongoing development plans for both immediate and far-future updates, and state the developer intends to work on M.A.S.S. Builder for as long as possible. New frames and systems are described as higher priority than any combat rework.
Post-1.0 'What's Next' post explicitly announces three upcoming features: PvP mode, new mech frames (Kickstarter stretch goals), and multi-unit photo mode. Developer commits to at minimum bimonthly updates and states development is continuing.
Content
1 of 1 released · no outstanding content
Media
Details
Developer
Publisher
Sekai Project
Achievements
—
Platform
Windows
Controller
full support
Steam Deck
Playable
Players
Single-player · Multiplayer · Co-op
About this game
“A future in where humans lived a prosperous century and technology advancing beyond space and time,” that was what humanity should have been if not for the sudden appearance of unknown beasts of the void. A large portion of humanity were gone in the moment. War for the survival of humanity broke off all over the world, changing landscapes and settlements into warzones. Humanity were forced to relocate into shelters and reinvent their technologies into weapons of war, the M.A.S.S. technology.
M.A.S.S. Builder is an Action RPG with players piloting a M.A.S.S. (Mechanical Assault Skeleton Suit) as a commander of a private military company, setting out to help combat the threat of Quarks. You will build, customize, and fight to save the world, or at least, have fun creating and customizing your perfect mechanical suits.
The game features an in-depth customization system that has a clear distinction between equipment that gives status and equipment of pure aesthetics. You will be able to customize everything to suit your playstyle while looking good in this fast-paced mechanical combat.
M.A.S.S. Builder is an Action RPG with players piloting a M.A.S.S. (Mechanical Assault Skeleton Suit) as a commander of a private military company, setting out to help combat the threat of Quarks. You will build, customize, and fight to save the world, or at least, have fun creating and customizing your perfect mechanical suits.
The game features an in-depth customization system that has a clear distinction between equipment that gives status and equipment of pure aesthetics. You will be able to customize everything to suit your playstyle while looking good in this fast-paced mechanical combat.
Key Features
- Customize your own M.A.S.S. without the worry of using cool looking armors with low stats, all parts don't have stats!
- Fast paced movement through the battlefield with boosters for you to move around and attack through your enemies.
- Fight against hordes of beastly aliens called Quarks, and giant ones that will aggressively hunt you down.
- Pick how your weapon looks and shoots with hundreds of parts available to mix and match.
- A world compelling and rich with information for you to immerse yourself in.
Are these done yet?
Last evaluated Jun 26, 2026
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