
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.
Modeled estimate, not a reported figure. How we estimate →
Prices
Each in the currency that store quoted — not converted: the gap between two rows is the publisher's pricing, not an exchange rate.
Every market we collect.
Discounts
Every price cut of more than 20% we have observed, in each market that quoted one, with this game's chart position on either side of it. These are episodes, not a model: a sale is one event, and one event cannot tell you what the next one will do.
Reviews, worldwide (the counter carries no country): 0.14/day in the week to Aug 17 → 0.43/day in the week after.
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Genres
Add-ons
Each DLC is estimated with the same model as a game, then summed — a modeled figure, not reported DLC sales.
Updates
Build ids and update times come straight from Steam's PICS — the same source SteamDB reads. Patch history grows as we record new builds.
Engagement
Reviews
Themes across 803 recent reviews and how positive each mention is. A keyword signal, not full sentiment analysis.
Reviews
汉化不行装备的东西描述看不懂
汉化不全👎👎👎
This game is still in early access and is still being constantly worked on and updated over the past 6 years. So it's not a perfect game, but the game devs haven't given up on this game and that speaks volumes. They are adding to the game with each update and constantly keep their players updated with regular updates. Is it perfect no? Do they keep working on it, to make it better with each update, HELL YES! I love the fact that this is still an active project and begin worked on. The best way to describe this game is an arcade version of Armored Core that focuses a lot in customization and fun and isn't overpriced. It is a real hidden gem on steam and recommend it to every mech fan. Just load the demo and give it a shot for yourself.
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Price dynamics, follower growth, revenue and sales trajectories with interactive tooltips
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For scale, across Steam · Top Sellers · Brazil over the last 30 days: the 24 chart moves that followed a price cut of more than 20% went a median of 9 places towards #1, and the 2,404 moves with no price cut behind them went 2 away. One store, one chart, one country — it is the only place we have enough observations to say even that.
Prices outside the United States have been collected since 6 August 2026 and chart positions since 19 July 2026, so a cut older than that has no market to compare and a market that joined later has no history yet. Nothing here is converted between currencies.
Stats
All-time low is the lowest price we've recorded for this game since we started tracking it.
Languages: English, Japanese, Simplified Chinese, Thai, Traditional Chinese
Hours played at review time, across 805 reviews with recorded playtime.
positive critical· bar length = how often the theme comes up
汉化做完全可以吗?真无语
they gave up
After nearly 50 hours of play time i must say that the story is incredible, dare i say even better than Evangelion. I must preface this though. I have never watched EVA nor have i paid any attention to the story of mass builder. IDK mech cool i guess ¯\_(ツ)_/¯
Mech building - 9/10 Dialog - Like sandpaper on my brain. The exposition dumping and writing style in general are so dry and the game expects you to read paragraph after paragraph. By the time I got to the mech customization screen my eyes had glazed over so I couldn't read how to actually customize my parts and colors.
快点加入创意工坊
Control is very clunky. Swapping between closed combat and ranged combat weapon isn't intuitive. At least mecha customization is cool and very detailed. If you're looking for a game, then don't buy this. Buy Armored Core or Gundam Breaker instead. But if you're looking for a mecha design tool, M.A.S.S Builder is the answer. Buy it on sale.
Great level of customisation but, most parts do pretty much nothing and are completely cosmetic, the gameplay feels a little janky and slow, and without doing anything out of the ordinary there was a bug that let me buy upgrades at no cost which kills the progression that makes games like these fun. there was a lot of potential here and I want these devs to succeed but in the games state I see no reason to play this over any installment in the armoured core franchise. I followed this game from it's early acces days and am really heart broken to see it not living up to it's full potential.
Players by region
Where this game's players are, estimated from review languages.
Players also reviewed
The games this title's players most often review too — audience affinity.
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