# Touhou Seirensen ~ Undefined Fantastic Object.

> What is that? A bird? A fairy? A mysterious, unidentified fantastical object invites you into an unknown world! A fantastic, retro bullet-hell shooter fantasy

## Game facts

- Developer: 上海アリス幻樂団
- Publisher: Mediascape Co., Ltd.
- Release status: Released
- Release date: Jun 6, 2020
- Region for this schedule: GLOBAL
- Platforms: PC
- Genres: Action, Shooting, BulletHell
- Steam Deck: Playable (Steam, checked Nov 4, 2026: https://store.steampowered.com/app/1100160/)
- Languages: Interface: Japanese (Japan); Subtitles: Japanese (Japan) (IGDB, checked Nov 4, 2026: https://www.igdb.com/games/touhou-seirensen-undefined-fantastic-object)

## AI Review Analysis

Analyzed Sep 2, 2026

### Strengths

- Unique and deep gameplay combining bullet-pattern dodging with UFO collection
- High difficulty that stimulates the desire for challenge, along with a strong sense of accomplishment upon clearing stages
- Highly praised, distinctive soundtrack and main menu music

### Weaknesses

- The resource system requiring players to manage UFO colors and appearance patterns can feel complex and unfair
- The difficulty is extremely high due to bosses' fast bullets and the need to handle multiple tasks simultaneously in some stages
- Certain spell cards and boss patterns can cause repeated frustration

## Links

- [Touhou Seirensen ~ Undefined Fantastic Object. on WAME](https://www.wame.is/game/4770)
- [Player reviews](https://www.wame.is/game/4770/reviews)

Updated: 2026-11-09T17:07:03.296Z