Overview
BlackFlagBreaker!! is a collaboration track between NIJISANJI virtual liver Kizuku Yashiro (社築) and veteran producer sasakure.UK, originally commissioned to celebrate Yashiro's fourth anniversary as a VTuber. The song was released with a full music video featuring illustrations by vivi, background art by PA-neguMA, title logo design by Rie Watanabe, and background animation by pam. It first entered the rhythm game world through CHUNITHM NEW PLUS in June 2022 before crossing over to maimai DX as part of the PRiSM PLUS update on June 20, 2025.
Musically, the track is driven by sasakure.UK's signature high-energy, glitch-inflected production, the composer is well known in the BMS (Be-Music Source) doujin scene and has contributed to numerous rhythm game franchises. Yashiro's vocals deliver lyrics that weave a narrative of digital rebellion: hacking through a programmed, oppressive reality, breaking "black flags" that symbolize despair and surrender. Terms like "trouble hacker," "program," and "unreasonable orders" reinforce a cyberpunk-tinged, anti-authoritarian energy that matches the track's relentless 163 BPM pace.
In its transition from CHUNITHM to maimai, the song received entirely independent chart arrangements. The maimai EXPERT chart, crafted by 鳩ホルダー (Hato Holder), and the MASTER chart by Luxizhel at level 13+ (constant 13.9) both demand tight execution across dense tap and slide patterns. The song is also associated with a title-earning challenge in maimai: playing BlackFlagBreaker!! alongside another specific track within a single credit unlocks the "社畜" (shachiku, meaning corporate slave) title, a wordplay on Yashiro's name.
Videos
Charts
DX
BASIC
4(4)
214 notesDesigner: -|Tap 186Hold 9Slide 5Touch 6Break 8
ADVANCED
8(8)
404 notesDesigner: -|Tap 349Hold 12Slide 15Touch 26Break 2
EXPERT
11(11)
588 notesDesigner: 鳩ホルダー|Tap 406Hold 50Slide 49Touch 41Break 42
MASTER
13+(13.9)
998 notesDesigner: Luxizhel|Tap 693Hold 112Slide 124Touch 27Break 42
Trivia
- BlackFlagBreaker!! was created to commemorate the fourth anniversary of Kizuku Yashiro (社築), a virtual liver affiliated with NIJISANJI.
- Composition, arrangement, and lyrics are by sasakure.UK, with mixing handled by Yu Aoki (B-PILOT). The music video features illustration by vivi, background art by PA-neguMA, title logo design by Rie Watanabe, and background animation by pam.
- The song debuted in SEGA's CHUNITHM NEW PLUS on June 23, 2022 (Asian version: October 27, 2022; Chinese version: March 28, 2024) before arriving in maimai DX PRiSM PLUS on June 20, 2025 (Asian version: October 30, 2025).
- In maimai, playing BlackFlagBreaker!! alongside the track 「人里に下ったアタイがいつの間にか社畜になっていた件」 within a single credit earns the title 「社畜」 (shachiku, 'corporate slave'), a kanji pun on Yashiro's name (社築).
- The CHUNITHM ADVANCED chart was designed by Techno Kitchen, who intentionally set its note count to 846, a goroawase (numerical wordplay) reading 'Yashiro' (8-4-6), and incorporated 8-4-6 rhythmic patterns into the chart.
- The CHUNITHM EXPERT chart's note count of 1,487 coincidentally matches the exact note count of the Single ANOTHER chart for the beatmania IIDX song 「音楽」, a chart Yashiro had famously full-comboed on stream. Charter アミノハバキリ (Aminohabakiri) confirmed the match was unintentional.
- The song's MASTER chart in CHUNITHM is level 14, making it one of the higher-difficulty charts in that game's POPS & ANIME category at the time of its release.
FAQ
- Who composed BlackFlagBreaker!!?
- The track was composed, arranged, and written by sasakure.UK, a veteran producer known for his work in the BMS doujin scene and contributions to multiple rhythm game series.
- Who sings BlackFlagBreaker!!?
- The vocals are performed by Kizuku Yashiro (社築), a virtual liver (VTuber) affiliated with NIJISANJI, for whom the song was created as a fourth anniversary celebration.
- When was BlackFlagBreaker!! added to maimai?
- It was added to maimai DX on June 20, 2025, as part of the PRiSM PLUS update, approximately three years after its original debut in CHUNITHM NEW PLUS.
- What difficulty is the MASTER chart for BlackFlagBreaker!! in maimai?
- The MASTER chart is rated level 13+ with a difficulty constant of 13.9, designed by Luxizhel with a total of 998 notes.
- Who designed the EXPERT chart for BlackFlagBreaker!! in maimai?
- The EXPERT chart was designed by 鳩ホルダー (Hato Holder) at level 11 with a constant of 11.0.
- What are the lyrics of BlackFlagBreaker!! about?
- The lyrics portray a protagonist hacking through a digitally programmed reality, rebelling against unfair orders and breaking through 'black flags' of despair. The imagery combines cyberpunk tropes with themes of resistance and perseverance.
- What does the in-game title 「社畜」 mean in relation to BlackFlagBreaker!!?
- 「社畜」 (shachiku) means 'corporate slave' in Japanese. It functions as a pun on Kizuku Yashiro's name (社築), as both share the kanji 社. Players earn this title by playing BlackFlagBreaker!! alongside a specific partner song in a single credit.
- Did BlackFlagBreaker!! appear in any other rhythm game before maimai?
- Yes, the song first appeared in SEGA's CHUNITHM NEW PLUS in June 2022, where its charts gained attention for numerological Easter eggs, the ADVANCED chart's 846 notes spell out Yashiro's name via goroawase.
