The Game Census
M.A.S.S. Builder cover art

M.A.S.S. Builder

Vermillion Digital · Sekai Project · 2025-09-14

Steam

ActionIndieRPGStrategy

Modes: Single player, Multiplayer, Co-operative

Releases: Sep 14, 2025 (PC (Microsoft Windows))

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.

15
playing now
85%
positive of 4.1k reviews
Very Positive
steam rating
100,000–200,000
owners (SteamSpy est.)
80/100
IGDB user rating (1 ratings)
gold
deck/linux tier (ProtonDB)
$24.99
steam price (US)

15 players in-game as of 2026-08-30 04:00 UTC (census sample)

M.A.S.S Builder is an RPG-mech-fighting video game developed by Thai studio The Vermillion Digital and published by Sekai Project. It was released for Microsoft Windows in 2019.

Health check

Quietly active
  • · 15 players in-game at the last census sample.
  • · 94 reviews in the last 8 weeks (~12/week).
  • · Review velocity down 28% vs the prior 8 weeks.
  • · Top 18% of 10,791 Action games in the census by review count.

Health tier since 2026-08-27

Estimated sales: 82k–185k copies

Review-multiple estimate from 4,121 total reviews — how this is computed.

Current store prices

lowest across shops (ITAD)$24.99

Deal snapshots via CheapShark, refreshed daily.

All-time low: $13.99 at GreenManGaming (2026-04-27) · bundled 1×via IsThereAnyDeal

12-month high $24.99 · on sale 15 of 33 observed days (census price snapshots)

Review momentum

PositiveNegative
22422420192026Week of 2019-09-01: 224 positiveWeek of 2019-09-01: 31 negativeWeek of 2019-10-01: 49 positiveWeek of 2019-10-01: 8 negativeWeek of 2019-11-01: 118 positiveWeek of 2019-11-01: 5 negativeWeek of 2019-12-01: 103 positiveWeek of 2019-12-01: 7 negativeWeek of 2020-01-01: 67 positiveWeek of 2020-01-01: 3 negativeWeek of 2020-02-01: 37 positiveWeek of 2020-02-01: 3 negativeWeek of 2020-03-01: 50 positiveWeek of 2020-03-01: 3 negativeWeek of 2020-04-01: 66 positiveWeek of 2020-04-01: 7 negativeWeek of 2020-05-01: 56 positiveWeek of 2020-05-01: 7 negativeWeek of 2020-06-01: 60 positiveWeek of 2020-06-01: 10 negativeWeek of 2020-07-01: 178 positiveWeek of 2020-07-01: 25 negativeWeek of 2020-08-01: 77 positiveWeek of 2020-08-01: 7 negativeWeek of 2020-09-01: 106 positiveWeek of 2020-09-01: 18 negativeWeek of 2020-10-01: 91 positiveWeek of 2020-10-01: 8 negativeWeek of 2020-11-01: 93 positiveWeek of 2020-11-01: 8 negativeWeek of 2020-12-01: 66 positiveWeek of 2020-12-01: 7 negativeWeek of 2021-01-01: 76 positiveWeek of 2021-01-01: 5 negativeWeek of 2021-02-01: 80 positiveWeek of 2021-02-01: 3 negativeWeek of 2021-03-01: 74 positiveWeek of 2021-03-01: 8 negativeWeek of 2021-04-01: 59 positiveWeek of 2021-04-01: 18 negativeWeek of 2021-05-01: 57 positiveWeek of 2021-05-01: 8 negativeWeek of 2021-06-01: 75 positiveWeek of 2021-06-01: 10 negativeWeek of 2021-07-01: 92 positiveWeek of 2021-07-01: 10 negativeWeek of 2021-08-01: 57 positiveWeek of 2021-08-01: 4 negativeWeek of 2021-09-01: 41 positiveWeek of 2021-09-01: 8 negativeWeek of 2021-10-01: 39 positiveWeek of 2021-10-01: 7 negativeWeek of 2021-11-01: 63 positiveWeek of 2021-11-01: 3 negativeWeek of 2021-12-01: 50 positiveWeek of 2021-12-01: 4 negativeWeek of 2022-01-01: 60 positiveWeek of 2022-01-01: 8 negativeWeek of 2022-02-01: 60 positiveWeek of 2022-02-01: 8 negativeWeek of 2022-03-01: 31 positiveWeek of 2022-03-01: 9 negativeWeek of 2022-04-01: 35 positiveWeek of 2022-04-01: 6 negativeWeek of 2022-05-01: 48 positiveWeek of 2022-05-01: 3 negativeWeek of 2022-06-01: 40 positiveWeek of 2022-06-01: 3 negativeWeek of 2022-07-01: 51 positiveWeek of 2022-07-01: 6 negativeWeek of 2022-08-01: 38 positiveWeek of 2022-08-01: 8 negativeWeek of 2022-09-01: 29 positiveWeek of 2022-09-01: 5 negativeWeek of 2022-10-01: 31 positiveWeek of 2022-10-01: 6 negativeWeek of 2022-11-01: 48 positiveWeek of 2022-11-01: 5 negativeWeek of 2022-12-01: 42 positiveWeek of 2022-12-01: 6 negativeWeek of 2023-01-01: 38 positiveWeek of 2023-01-01: 5 negativeWeek of 2023-02-01: 23 positiveWeek of 2023-02-01: 3 negativeWeek of 2023-03-01: 32 positiveWeek of 2023-03-01: 10 negativeWeek of 2023-04-01: 19 positiveWeek of 2023-04-01: 2 negativeWeek of 2023-05-01: 31 positiveWeek of 2023-05-01: 7 negativeWeek of 2023-06-01: 18 positiveWeek of 2023-06-01: 3 negativeWeek of 2023-07-01: 18 positiveWeek of 2023-07-01: 3 negativeWeek of 2023-08-01: 24 positiveWeek of 2023-08-01: 7 negativeWeek of 2023-09-01: 19 positiveWeek of 2023-09-01: 5 negativeWeek of 2023-10-01: 18 positiveWeek of 2023-10-01: 8 negativeWeek of 2023-11-01: 24 positiveWeek of 2023-11-01: 2 negativeWeek of 2023-12-01: 18 positiveWeek of 2023-12-01: 5 negativeWeek of 2024-01-01: 12 positiveWeek of 2024-01-01: 7 negativeWeek of 2024-02-01: 8 positiveWeek of 2024-02-01: 1 negativeWeek of 2024-03-01: 16 positiveWeek of 2024-03-01: 3 negativeWeek of 2024-04-01: 19 positiveWeek of 2024-04-01: 7 negativeWeek of 2024-05-01: 25 positiveWeek of 2024-05-01: 14 negativeWeek of 2024-06-01: 12 positiveWeek of 2024-06-01: 3 negativeWeek of 2024-07-01: 22 positiveWeek of 2024-07-01: 3 negativeWeek of 2024-08-01: 21 positiveWeek of 2024-08-01: 4 negativeWeek of 2024-09-01: 5 positiveWeek of 2024-09-01: 1 negativeWeek of 2024-10-01: 8 positiveWeek of 2024-10-01: 5 negativeWeek of 2024-11-01: 6 positiveWeek of 2024-11-01: 2 negativeWeek of 2024-12-01: 14 positiveWeek of 2024-12-01: 4 negativeWeek of 2025-01-01: 5 positiveWeek of 2025-01-01: 3 negativeWeek of 2025-02-01: 3 positiveWeek of 2025-02-01: 4 negativeWeek of 2025-03-01: 9 positiveWeek of 2025-03-01: 5 negativeWeek of 2025-04-01: 6 positiveWeek of 2025-04-01: 4 negativeWeek of 2025-05-01: 7 positiveWeek of 2025-05-01: 5 negativeWeek of 2025-06-01: 8 positiveWeek of 2025-06-01: 4 negativeWeek of 2025-07-01: 3 positiveWeek of 2025-07-01: 6 negativeWeek of 2025-08-01: 9 positiveWeek of 2025-08-01: 2 negativeWeek of 2025-09-01: 27 positiveWeek of 2025-09-01: 20 negativeWeek of 2025-10-01: 11 positiveWeek of 2025-10-01: 2 negativeWeek of 2025-11-01: 11 positiveWeek of 2025-11-01: 6 negativeWeek of 2025-12-01: 4 positiveWeek of 2025-12-01: 5 negativeWeek of 2026-01-01: 7 positiveWeek of 2026-01-01: 5 negativeWeek of 2026-02-01: 2 positiveWeek of 2026-02-01: 3 negativeWeek of 2026-03-01: 9 positiveWeek of 2026-03-01: 4 negativeWeek of 2026-04-01: 8 positiveWeek of 2026-04-01: 5 negativeWeek of 2026-05-01: 5 positiveWeek of 2026-05-01: 2 negativeWeek of 2026-06-01: 10 positiveWeek of 2026-06-01: 13 negativeWeek of 2026-07-01: 5 positiveWeek of 2026-07-01: 7 negativeWeek of 2026-08-01: 5 positiveWeek of 2026-08-01: 6 negative
Weekly review counts (Steam review histogram). Positive above the line, negative below.

Players online

2322026-08-11 18:00 — 11 players2026-08-12 10:00 — 10 players2026-08-13 02:00 — 7 players2026-08-13 18:00 — 8 players2026-08-14 09:00 — 11 players2026-08-15 01:00 — 13 players2026-08-15 17:00 — 11 players2026-08-16 09:00 — 10 players2026-08-17 01:00 — 8 players2026-08-17 17:00 — 6 players2026-08-18 09:00 — 16 players2026-08-19 01:00 — 19 players2026-08-19 16:00 — 19 players2026-08-20 08:00 — 8 players2026-08-21 00:00 — 23 players2026-08-21 16:00 — 19 players2026-08-22 07:00 — 21 players2026-08-22 23:00 — 20 players2026-08-23 15:00 — 18 players2026-08-24 07:00 — 18 players2026-08-24 23:00 — 13 players2026-08-25 14:00 — 20 players2026-08-26 07:00 — 2 players2026-08-26 23:00 — 7 players2026-08-27 15:00 — 10 players2026-08-28 05:00 — 9 players2026-08-28 21:00 — 6 players2026-08-29 12:00 — 9 players2026-08-30 04:00 — 15 players
Concurrent players, hourly average, last 30 days (census samples).

Price history

$24.99$14.522019-09-132026-08-242019-09-13 — best price $22.492019-11-10 — best price $22.492020-01-23 — best price $21.242020-05-25 — best price $24.992020-07-20 — best price $19.992020-11-07 — best price $21.242021-02-11 — best price $19.992021-04-30 — best price $18.062021-07-15 — best price $21.242021-08-05 — best price $21.242021-10-28 — best price $19.992021-12-01 — best price $24.992022-01-24 — best price $16.992022-03-21 — best price $16.992022-05-13 — best price $16.572022-06-24 — best price $21.242022-08-08 — best price $24.992022-11-14 — best price $16.992022-12-22 — best price $21.242023-03-06 — best price $24.992023-05-06 — best price $24.992023-08-07 — best price $24.992023-11-04 — best price $24.992023-12-11 — best price $24.992024-01-25 — best price $21.242024-02-27 — best price $24.992024-05-06 — best price $21.242024-07-12 — best price $24.992024-09-30 — best price $24.992024-12-13 — best price $15.992025-03-03 — best price $15.992025-05-09 — best price $15.992025-07-25 — best price $17.632025-09-25 — best price $16.992025-12-12 — best price $15.992026-03-03 — best price $24.992026-05-05 — best price $24.992026-06-25 — best price $17.492026-08-24 — best price $24.99
Lowest recorded price across tracked stores, per day (census snapshots).

Attention

6212026-05-30 — 8 pageviews2026-06-02 — 5 pageviews2026-06-05 — 5 pageviews2026-06-08 — 11 pageviews2026-06-11 — 5 pageviews2026-06-14 — 7 pageviews2026-06-17 — 20 pageviews2026-06-20 — 4 pageviews2026-06-23 — 3 pageviews2026-06-26 — 20 pageviews2026-06-29 — 9 pageviews2026-07-02 — 7 pageviews2026-07-05 — 10 pageviews2026-07-08 — 8 pageviews2026-07-11 — 9 pageviews2026-07-14 — 6 pageviews2026-07-17 — 4 pageviews2026-07-20 — 7 pageviews2026-07-23 — 7 pageviews2026-07-26 — 4 pageviews2026-07-29 — 1 pageviews2026-08-01 — 5 pageviews2026-08-04 — 13 pageviews2026-08-07 — 2 pageviews2026-08-10 — 2 pageviews2026-08-13 — 7 pageviews2026-08-16 — 6 pageviews2026-08-19 — 9 pageviews2026-08-22 — 10 pageviews2026-08-25 — 2 pageviews2026-08-27 — 5 pageviews
Daily Wikipedia pageviews (attention proxy, census-recorded).

Details

WindowsFull controller supportSingle-playerMulti-playerCo-opOnline Co-opFull controller supportSteam CloudFamily Sharing1 DLC

5 supported languages: English, Japanese, Simplified Chinese, Thai, Traditional Chinese

Player tags

RPGAnimeIndieMechsActionRobotsSci-fiShooterAction RPGFuturistic

Census log

Computed from census-recorded observations only — dates are observation dates.

Recent updates

Players also track

Star Control®: OriginsSurvivalistReverse CrawlForce of NatureUnbound: Worlds ApartRebel Galaxy OutlawTorchlight III

Similarity via IGDB.

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