Overview
おこちゃま戦争 (Okochama Sensou, "Childish War") brings together two defining figures of the 2010s Vocaloid scene: producer Giga-P and lyricist Reol. Built around a theatrical back-and-forth between Kagamine Rin and Len, the song casts the twin Vocaloids as aristocratic brothers locked in a petty, competitive feud, trading insults, boasting about status, and escalating their mock battle over Giga's driving electronic production. The title itself, a playful compound of "okochama" (a cutesy, honorific-laden term for a child) and "sensou" (war), sets the tone for the lyrical wordplay.
The track first appeared on the 2014 compilation album Download feat. 初音ミク, accompanied by an animated music video by illustrator Okiku. It was added to maimai at the launch of maimai ORANGE on September 18, 2014, classified under the niconico & VOCALOID genre. The maimai version runs approximately 1:58, omitting the song's fourth verse section. Over successive maimai versions, both the Master and Expert charts have been recalibrated multiple times, the Master chart (designed by はっぴー) rose from level 11 to 13 (constant 13.3), and the Expert chart (designed by 某S氏) moved from level 9 to 10+ (constant 10.6), reflecting the charts' sustained demand on players as community skill levels evolved.
Outside of maimai, おこちゃま戦争 appears in SEGA's other rhythm game franchises CHUNITHM AIR PLUS (added March 2017) and オンゲキ. The track has also inspired a self-cover duet by Reol and kradness, as well as a unit cover by Wonderlands x Showtime in Project SEKAI Colorful Stage! feat. 初音ミク.
Videos
Charts
Trivia
- The song was composed and arranged by Giga-P (Giga), a prolific Vocaloid producer known for hits including Gimme×Gimme, Plus Danshi, and Chikyuu Saidai no Daisakusen.
- The lyrics were written by Reol, who later transitioned from Vocaloid lyricist and vocalist to a mainstream solo career with major-label releases.
- The track uses the Kagamine Rin and Len voice banks in a duet format that mirrors the sibling rivalry theme of the lyrics.
- The animated music video was created by illustrator and animator Okiku.
- おこちゃま戦争 was originally released on the 2014 compilation album Download feat. 初音ミク.
- The maimai edit runs 1:58, omitting the fourth verse section that is present in the full version and in the CHUNITHM and オンゲキ cuts (which run 2:20).
- The Master chart, designed by longtime maimai charter はっぴー, has undergone five level revisions across maimai versions: 11 (ORANGE), 11+ (MURASAKi), 12 (FiNALE), 12+ (DX+), and finally 13 (UNiVERSE+ onward).
- The Expert chart was designed by 某S氏 (Bou S shi, literally 'a certain Mr. S'), a charter identity that appears on several maimai ORANGE-era Expert charts.
- In Asian releases of maimai, the song title was displayed as Okocyama Sensou and the artist as Giga/Reol.
- The song was temporarily unavailable in the Chinese 舞萌DX (maimai DX) cabinet release but was restored in the 舞萌DX 2021 update.
- A self-cover duet of おこちゃま戦争 performed by Reol and kradness was posted on kradness' YouTube channel.
- The song received a unit cover by Wonderlands x Showtime (featuring Kagamine Rin and Len) in Project SEKAI Colorful Stage! feat. 初音ミク.
- おこちゃま戦争 was added to CHUNITHM AIR PLUS on March 9, 2017, and was eventually delisted from the Asian version of CHUNITHM NEW before returning in CHUNITHM LUMINOUS.
FAQ
- Who composed and wrote おこちゃま戦争?
- The song was composed and arranged by Giga-P (Giga), with lyrics written by Reol. The vocals are performed by the Kagamine Rin and Len Vocaloid voice banks.
- What does おこちゃま戦争 mean in English?
- おこちゃま戦争 (Okochama Sensou) translates roughly to 'Childish War' or 'Kids' War,' referencing the playful aristocratic sibling rivalry depicted in the lyrics.
- When was おこちゃま戦争 added to maimai?
- It was added at the launch of maimai ORANGE on September 18, 2014.
- What are the current difficulty levels for おこちゃま戦争 in maimai?
- As of maimai DX FESTiVAL and later versions, the standard charts are: Basic 6, Advanced 7, Expert 10+ (constant 10.6), and Master 13 (constant 13.3).
- Who designed the maimai Expert and Master charts for おこちゃま戦争?
- The Expert chart was designed by 某S氏, and the Master chart was designed by はっぴー.
- What other rhythm games feature おこちゃま戦争?
- The song also appears in CHUNITHM AIR PLUS (added March 2017) and オンゲキ, both developed by SEGA.
- What album is おこちゃま戦争 from?
- The song was originally released on the 2014 compilation album Download feat. 初音ミク.
- Does the maimai version of おこちゃま戦争 include all the lyrics?
- No, the maimai version is a shortened edit approximately 1:58 in length, omitting the song's fourth verse section that appears in the full version and in other game cuts.
