The Game Census
東方星蓮船 〜 Undefined Fantastic Object. cover art

東方星蓮船 〜 Undefined Fantastic Object.

上海アリス幻樂団 · Mediascape Co., Ltd. · 2020-06-05

Steam

ActionIndie

Franchise: Touhou Project · Modes: Single player

Releases: Aug 15, 2009 (PC (Microsoft Windows))

アレは何だ？　鳥か？　妖精か？ 謎に満ちた未確認幻想物体が、君を未知の世界に誘う！ ファンタスティックでレトロな弾幕シューティング幻想

5
playing now
96%
positive of 446 reviews
Very Positive
steam rating
50,000–100,000
owners (SteamSpy est.)
80/100
IGDB user rating (7 ratings)
platinum
deck/linux tier (ProtonDB)
$14.99
steam price (US)

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

Touhou Seirensen ~ Undefined Fantastic Object. is the twelfth main game of the Touhou Project scrolling shooter series, by dōjin game circle Team Shanghai Alice. The game was released at the 76th Comiket on August 15, 2009, and then followed by a retail release on September 11, 2009, at doujinshi stores. Undefined Fantastic Object was the first Touhou game to introduce colored power-ups, which reward the player with extra lives, points and bombs when collected, a gameplay mechanic that would be used in multiple games later on in the series.

Health check

Insufficient data
  • · Not enough review history collected yet to judge health.
  • · Top 47% of 10,791 Action games in the census by review count.
Estimated sales: 8.9k–20k copies

Review-multiple estimate from 446 total reviews — how this is computed.

All-time low: $10.49 at Steam (2025-08-17)via IsThereAnyDeal

12-month high $14.99 · on sale 1 of 2 observed days (census price snapshots)

Players online

1932026-08-11 22:00 — 3 players2026-08-12 13:00 — 19 players2026-08-13 05:00 — 9 players2026-08-13 21:00 — 5 players2026-08-14 13:00 — 9 players2026-08-15 05:00 — 12 players2026-08-15 21:00 — 7 players2026-08-16 13:00 — 11 players2026-08-17 05:00 — 6 players2026-08-17 20:00 — 6 players2026-08-18 12:00 — 14 players2026-08-19 04:00 — 8 players2026-08-19 20:00 — 4 players2026-08-20 11:00 — 13 players2026-08-21 03:00 — 8 players2026-08-21 19:00 — 9 players2026-08-22 11:00 — 14 players2026-08-23 02:00 — 6 players2026-08-23 18:00 — 10 players2026-08-24 10:00 — 7 players2026-08-25 02:00 — 11 players2026-08-25 18:00 — 4 players2026-08-26 10:00 — 12 players2026-08-27 02:00 — 6 players2026-08-27 18:00 — 4 players2026-08-28 10:00 — 5 players2026-08-29 02:00 — 6 players2026-08-29 16:00 — 12 players2026-08-30 08:00 — 5 players
Concurrent players, hourly average, last 30 days (census samples).

Price history

$14.99$10.492020-06-062026-06-152020-06-06 — best price $14.992025-08-17 — best price $10.492025-08-24 — best price $14.992026-06-08 — best price $10.492026-06-15 — best price $14.99
Lowest recorded price across tracked stores, per day (census snapshots).

Details

WindowsSingle-playerSteam CloudFamily Sharing

1 supported languages: Japanese

Player tags

2DAnimeFaithIndieActionArcadeDifficultBullet HellShoot 'Em UpSingleplayer

Census log

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

Players also track

Momodora: Reverie Under The MoonlightCelesteTouhou Luna Nights東方神霊廟 〜 Ten Desires.東方鬼形獣 〜 Wily Beast and Weakest Creature.東方風神録 〜 Mountain of Faith.

Similarity via IGDB.

Wikipedia ↗Official site ↗