- Hanaemonster (Founding member)
- Nao Of Nao (Founding member)
- Aika The Spy (Founding member)
- Miyukiangel (Founding member)
- Kaedephoenix (Joined December 25th, 2019)
- Yuki Reysole (Temporary member)
In August 2019, an audition for a new WACK unit was held, with variety show comedian Kuro-chan being heavily involved with the process. The audition camp was filmed and later broadcast as the miniseries MONSTER IDOL, from November 6 to December 18.
After the episode broadcast, their debut music video for lead single "Restart" was posted on Tower Records' YouTube page, followed by an announcement that the single would go on sale tomorrow. For promo, members of the group (and Kuro-chan) visited Tower Records stores around the country to meet prospective fans.
On December 25, MAMESHiBA NO TAiGUN held their debut live, where not only was it announced that Kuro-chan would be dismissed as their producer, but also that MONSTER IDOL runner-up Kaede would join the group.
On January 1, all MAMESHiBA NO TAiGUN members changed their stage names; Aika's name was extended to Aika The Spy, Nao to Nao Of Nao, Miyuki to Miyukiangel and Kaede to Kaedephoenix. Hanae reverted to her former WAgg stage name, Hanaemonster. Along with these name changes also brought a change in image, with leather sukeban-inspired costumes suggesting an edgier and more "WACK-like" rebranding compared to the traditional idol appearance of their debut single. This upset a vocal portion of MAMESHiBA's fanbase, who complained to Watanabe about the changes and demanded Kuro-chan's rehiring.
Towards the end of January, MAMESHiBA NO TAiGUN opened their official YouTube channel, and announced that they would release their second single in the near future.
On February 12, a special reunion episode of MONSTER IDOL aired where Watanabe and Kuro-chan announced the next singles and sales campaign: Kuro-chan Vs WACK. If the music video for the Kuro-chan written and produced song Rocketstart gains more views on YouTube by 11pm on February 19 than the WACK written and produced song Daijoubu Sunrise, then Kuro-chan will be reinstated as the full-time producer. The music videos for the two songs dropped instantly after the show's broadcast. The following week, it was announced that Rocketstart had gained more YouTube views and Kuro-chan was reinstated as their producer.
On March 8, MAMESHiBA NO TAiGUN announced that they would release their debut album, Start, and hold their debut oneman live on May 13. However, due to the COVID-19 outbreak prompting a state of emergency in Japan, the album release was delayed to June 10.
On May 14, the day after what would have been Start's original release date, MAMESHiBA NO TAiGUN released the digital single, FLASH while also revealing more information about the album. It was followed up by Donkusa Happy on the 27th.
During an episode of Suiyobi no Downtown aired on August 5, it was announced that MAMESHiBA NO TAiGUN would make their major label debut under Avex, the same company as BiSH and EMPiRE. The music video for their first song, SAMABARi, was revealed the same day. The following month, B-side KOi NO KAKEZAN ABCDEFG was also released.
MAMESHiBA NO TAiGUN's debut single, AAA, was released on October 7.
MAMESHiBA NO TAiGUN held a live "sports day" event at Tokyo Dome on October 11. As the name suggests, all members competed against each other in a series of sporting events. The sports day was broadcast live on their YouTube channel. At the end of the event, MAMESHiBA NO TAiGUN announced their first nationwide tour to take place from December to January.
On October 24, MAMESHiBA NO TAiGUN held their first one-man live. During the performance, they announced their second album, MAMEJOR! to be released in January 2021, and a photobook commemorating their first anniversary.
Throughout November and December, MAMESHiBA NO TAiGUN began releasing tracks from MAMEJOR! as digital singles, starting with ONEGAi KiSS ME on November 16. MAME NO UTA, MOTiON and TO THE FUTURE followed in the following weeks.
MAMESHiBA NO TAiGUN's first photobook, Hatsuga, was released on December 19. Two days later, a digital EP compiling all of their digital singles from MAMEJOR! so far, Boku Dake no Kaito, was released.
In late 2020, MAMESHiBA NO TAiGUN were nominated for "New Artist Of The Year" at the Japan Record Awards. While they did not win, they attracted attention and controversy during the December 30th award ceremony, when the actual winner, Sanada Naoki, was declared. In response to the announcement, member Miyukiangel jumped in the air and "collapsed", with the remaining members carrying her offstage. The stunt attracted heavy criticism from viewers who felt that they had stolen attention away from the winner.
MAMESHiBA NO TAiGUN's major debut album, MAMEJOR!, was released on January 10.
In an episode of Suiyobi no Downtown aired on February 3, MAMESHiBA NO TAiGUN's next release was announced for some time in the future, with the revelation that a special guest vocalist would feature on the track. Some selected options included Dempagumi Inc's Moga Mogami, SKE48's Matsui Jurina, and First Summer Uika. The conditions of who would feature on the new song would be determined on how much weight Kuro-chan could lose within a month. The following week, it was revealed that Kuro-chan had reached the target that would allow MAMESHiBA NO TAiGUN to perform with First Summer Uika, and the digital single and music video for the song, LOVE CHiKYU feat. First Summer Uika, was released on February 11.
In early April, it was announced that AKB48 member Kashiwagi Yuki (as Yuki Reysole) would be joining MAMESHiBA NO TAiGUN temporarily sometime in the near future. During the announcement, Yuki, who had previously starred on variety shows with Kuro-chan, expressed bemusement at the prospect of having to work with him again.
In May, it was announced that MAMESHiBA NO TAiGUN would release a single with Yuki Reysole, Zutto ki ni Naru Zucchini, on August 31st, concurrently with six other singles that she would feature in across various WACK groups. While initially scheduled for August 31st, in early June the single was postponed so that Yuki could receive emergency surgery.
On June 18th, MAMESHiBA NO TAiGUN released the digital single, MAMESUMMER!?
WOW!! Season was released on July 14th.
- [2019.11.06 - 2019.12.18] MONSTER IDOL
|10/25||MAMESHiBA NO TAiGUN no ReRestart||Showa Joshi Daigaku Hitomi Kinenkoudou, Tokyo||Debut oneman live (but not their first performance altogehter; see "Other")
Livestreamed on PIA.
|11/21-01/10||Jitsuryoku wo Shikkari to Tsukeru Tour|
|05/05-07/15||Mameshiba Daisakusen ~Tsukami Tore Mametsubu no Taigun~|
|10/03||MAMESHiBA NO TAiGUN No Shippou||Maihama Ampitheater, Chiba|
|01/03||WACK Nari no Koshien (WACKなりの甲子園)||Akasaka BLITZ, Tokyo||With all other WACK groups.|
|08/08||"WACK FUCKiN' SORRY PARTY"|
|November 4||Suiyoubi no Downtown
|Tokyo||Debut performance (televised as part of an episode of Suiyobi no Downtown)
Kuro-chan is (temporarily) fired and Kaedephoenix's membership is announced.
|October 4||Tokyo Idol Festival Online 2020||Tokyo||Event appearance; see also WACK presents DREAMLIGHTS in TIF|
|October 11||Dai Undoukai (大運動会; Big Sports Day)||Tokyo Dome||Sporting event. Was livestreamed on MAMESHiBA NO TAiGUN's YouTube channel.|
- Nao Of Nao and Kaedephoenix were both former members of iDOL STREET's trainee unit, street-sei, and it's subgroup, SAPPORO Snow♥Loveits.
- Including Hanaemonster, who was a member of WAgg, there are a total of three idol trainees in MAMESHiBA NO TAiGUN.
- Only Aika The Spy have not been in any other idol units.
- Hanaemonster and Nao Of Nao both previously participated in the WACK AUDiTiON CAMP 2019 together.
- Due to the audition being televised on a mainstream programme, MAMESHiBA NO TAiGUN have had the most commercially successful debut out of any other WACK group so far.