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…
85%of 4,130 Steam reviews— Very Positive85% of 4,130 Steam reviews are positive — Very Positive
Details
- Developer
- Vermillion Digital
- Publisher
- Sekai Project
- Released
- Sep 14, 2025
- Price
- $24.99
- Platform
- PC
Multiplayer
- Online co-op
- Yes
- Split screen co-op
- Not listed
- LAN co-op
- Not listed
- Crossplay
- Not listed
- Remote Play Together
- Not listed
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.

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.

This A+ Indie Mecha RPG Is Finally Out In 1.0! - M.A.S.S. Builder
Wanderbots

M.A.S.S. Builder - Gameplay
Game Mojo

The Mech Game That Wastes Its Best Idea - M.A.S.S. Builder
Kei-Nova

Does It Hold Up Now That It's Out? - M.A.S.S. Builder
Averis

M.A.S.S. Builder | Full Release 1.0.0. LAUNCH! | Gameplay PC
MAZAVS - Games Channel

M.A.S.S. Builder Feels Like Piloting Your Own Mech Anime Dream!
Gaming Plus TV
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