
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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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
This game has the best customization options, but unfortunately the combat is extremely underwhelming. This review is only rated positive due to the great customization system in spite of the combat/gameplay. Pros: - Most customization options compared to any other mech game so far. Accessories can be scaled and transformed to make several shapes and designs. - Photography mode to showcase your designs with different poses and backgrounds. - Huge amount of accessories/models to select from. Cons: - Unfortunately a pretty major one. Both melee and ranged weapons lack the feeling of any weight behind them. It feels like you're hitting enemies with a wet noodle. Despite the game putting a heavy emphasis on a hack and slash melee style, you will almost never realistically be able to execute a full combo without constantly taking hits because several common enemies do get interrupted or stunned by your own melee attacks. This remains true even after a recent buff to melee attack speed. - Ranged weapon builds also received huge nerfs along with many bosses (and some elite enemy units) receiving shields which are impervious to ranged weapons. In some cases there are little gaps you can shoot through to hit enemies, but even then you're barely going to do any damage. Ammo is also limited. Enemies are supposed to drop ammo if you kill enough of them, but the drops feel very inconsistent and bullet sponges can outright make guns nonviable. - Controls can feel a little janky at times especially when dodging. Using thrusters will force your mech to move towards your crosshair even if you are trying to strafe or move backwards sometimes. - You have to play the game to unlock parts for mech customizaiton. - There is no official support for sharing mech builds and designs. The only current way to do this is through use of third party software to extract the save files of your mechs and manually upload them online. Most people post their saves onto the unofficial MASS Builder Community Discord server (not to be confused with the Discord server of Sekai Project).
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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 26 chart moves that followed a price cut of more than 20% went a median of 7 places towards #1, and the 2,402 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
Combat is generic and unfulfilling. Coop is junk. There needs to be more done for this to be fun and after 5 years of EA, I think it's fair to say the dev's haven't delivered on the promise and premise of this game.
まず、アクションゲームとしては非常に大味である。 プレイヤーの腕でどうこうするより、性能を高めて殴るほうの比重が高い。 少なくとも、攻撃力のパラメータが足りないとロクに与ダメが通らずゲームにならない。 "ぼくのかんがえたさいきょうにかっこいいロボ"を作るゲームとしては最高である。 パーツの種類も多いし、部位も細かく分かれているし、アクセサリーを盛ることも可能。 ここが本作最大の開き直……もとい、ユニークなポイントであるが、 装甲(=ロボの外見)が性能に、一切、マジで、なにひとつ、影響を及ぼさない。 性能はエンジンやOSといった内部要素で決まるので、 つよさとかっこよさを秤にかけて不本意なパーツを選ぶ必要がないのである。 総合的に身も蓋もない言い方をするなら、 何ンダムブレーカーに近い方向性で、より振り切った感じと言えるかもしれない。 美少女も出る。幻覚ではなく。イケメンはどうかな……
汉化不全👎👎👎
Horrible combat for such a good builder
*优点: 1.高度自由的外观自定义 2.尚可一用的摄影模式 *缺点: 1.更新速度过慢,而且除关卡之外的内容(包含自定义部分)长期得不到更新 2.武装自由度低,限制了玩家的创造能力 3.烦人的单一游玩方式,且大量重复内容,游玩体验单一而且枯燥乏味 4.系统完成度低,大量疑似基础游戏系统的功能存在而不能并用 5.优化差劲,性能消耗大而画面、声效方面表现均不出色 6.粘滞的操作手感,明显的操作延迟与迟钝的角色动作 7.不公平的游戏平衡与挑战性,敌人如同狂战士般无畏而且不知疲倦,而完成关卡也毫无成就感可言 8.玩家资源始终有限,不是所有游玩风格都适合游玩 9.多人模式网络不稳定,而且读取速度慢 10.作为一款机器人游戏,游戏的重心似乎不在机器人上
It was fun... for the first 3 hours. And while building your own mech is still cool, gameplay is mid, while the story... is confusing. On top of that, this feels like the game was abandoned, no real updates in almost a year as of now. On top of that, the price tag is kind of high for this game. Its $25 USD last I looked, if this was a $10 game, THEN I would give it a thumbs up. BUT, that is not the case. I'll keep an eyes on it in case of more updates, but as now, uninstalling to make room for other games. It was fun, but not prolonged fun. I'd called it 'over-priced-short' fun.
The customization is very deep. If you are looking for a game in which you can build and pose mechs, then this will suffice. If you have the desire for a game in which you can pilot a mech with satisfying or fun combat. It will not suffice.
basically abandonware but they show up every once in a while to make "announcements" just so it doesn't get marked as such. even their Discord is lacking and they get mad if you have any criticism or questions which is concerning considering it's their only way of communicating. if they ever give the updates they promised, I'll change this to positive. update, they've released at least 10 visual novels since the last update to this game and a full action fighting game that's borderline fraudulent and should be reported as such. scummy devs can do nothing but scam and run away with your money. not worth $5 let alone $25
まだ途中までしかやってませんが、良くも悪くもカスタマイズが全てと感じました。 タイトルなど部分的に日本語対応していますが、ストーリー部分は日本語に対応していません。 アクションに関しては基本的に雑魚を倒し、ステージの最後にボスを倒していく感じです。 ボス戦では移動できる範囲が制限され、雑魚敵が4体出てきます。ボス戦の雑魚敵を一定数倒すと無限湧きになり、アイテムドロップもしなくなります。 特筆すべきは敵の固さです。特にボスはシールドを破壊するもしくは体幹?みたいな物を削りきらないとHPが減りません。そのくせHPも多く、体幹を削った後はダウン後にシールドが全回復します。 うまく立ち回れればうまく出来るのかもしれないんですが、自分にはちょっと分からなかったです。 総じてアクションにそれほどの面白みは無く、ストーリーも少し英語が分かる程度では文章量が多く疲れます。 ただし、ロボのカスタマイズはかなり細かくでき、キャラクリみたいなのが好きな人には楽しめるのかなと思いました。
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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