In October 2018, Babymetal announced that Yui Mizuno had decided to leave the band due to poor health after having been absent from live performances since December 2017.

"[6] According to Kobametal, Yui Mizuno and Moa Kikuchi were added to the band to complement Nakamoto's "unique stage presence" with their smaller statures, dancing around her "like angels".

[26] The single also included the song "Onedari Daisakusen" (おねだり大作戦, "Begging Operation") performed by Yuimetal and Moametal under the stage name of Black Babymetal.

[51] After the UK leg of the tour, the band went on to make their debut appearance in the United States on July 27 with a headlining show at The Fonda Theatre in Hollywood.

[52] They played Heavy Montréal 2014 in Canada on August 9 alongside Metallica, Slayer and Anthrax; and performed at Summer Sonic 2014 in Japan on the Mountain Stage with bands such as Avenged Sevenfold and Megadeth.

[53][54] Babymetal was also the opening act to five of Lady Gaga's concerts in her ArtRave: The Artpop Ball 2014 tour in August along the western United States.

The band made a point to provide a wide variety of styles to attract a wider audience and performed a full song in English.

[74][75] On July 18, the band made a special appearance at the Alternative Press Music Awards where they performed "Karate" before being joined onstage by Judas Priest frontman Rob Halford.

[78] In September 2016, Warner Bros. announced that a hybrid live action-animation fantasy-adventure short form series featuring the members of the band was under development.

[82] During their final show on the tour, Red Hot Chili Peppers drummer Chad Smith joined Babymetal onstage to perform their covers of Judas Priest's "Painkiller" and "Breaking the Law".

"[105] Mizuno remained absent for the rest of their tour, until their agency announced at a shareholders' meeting in June that she had been in poor health since December 2017, and was "currently recovering".

[132] In 2020, Babymetal was featured as a guest artist on Bring Me the Horizon's EP Post Human: Survival Horror, on the song "Kingslayer".

Japan ahead of the airing determined that the most anticipated song of the night was Babymetal's performance of "Ijime, Dame, Zettai", with 26.3% of the vote.

[149] They released the song "Light And Darkness" on February 23 with an accompanying music video, which likewise consisted of footage from their concerts at Makuhari Messe.

[155][154] Babymetal's concert at Makuhari Messe in January sparked fan speculation about a potential third member joining the band,[149] with Momoko Okazaki being a popular contender.

[169] To be specific, the body image concerns of girls and women pressured by society to remain thin and also bullying, while they also sing about what it is like going to your first concert, the concept of an "ideal woman" and chocolate, subjects which critics say are a step away from typical lyrical styles used by most metal bands.

While they remarked on the band sharing many similarities with other idol groups, they also commented on Su-metal's vocal delivery being markedly different from them, as she demonstrates a "strong voice with clear tone and a minimal amount of coloratura or embellishment".

The more extensive usage of English vocabulary in Metal Resistance Kennedy saw as an effort from the band to internationalize the themes of their album to reach a wider audience.

Babymetal's costumes take a variety of cues from the popular Japanese Gothic and Punk Lolita styles, with an emphasis on red and black.

[5] Additionally, Babymetal style of moshing, known as mosh'sh (モッシュッシュ, mosshusshu), has been described a safe, fun, friendly game of push and shove.

In their early stages, the backing band consisted of the "Babybones"—a group of nameless individuals dressed in skeleton costumes that would mime live performances while pre-recorded studio tracks were being used.

Starting in 2019, the Kami Band has featured primarily Western musicians; guitarists Chris Kelly and CJ Masciantonio, bassist Clint Tustin, and drummer Anthony Barone.

went viral in 2014 with USA Today's Brian Mansfield commenting that the "video looks like some kind of bizarre animé, with a dark-goth set and band members playing in skeleton costumes, and the three girls execute intricate choreography, flash heart signs and make windmill arm motions like they're playing air guitar"[196] In regards to their music video for the song "Karate", Moametal said that she is "very proud that they are now representing this culture that came from Japan through their music, and it's a way for more people outside of Japan to also learn what karate is all about.

By purchasing the binder and entering a code included with the enclosed art book online, one could join the band's official fanclub called "Babymetal Apocalypse Web".

[205] A video uploaded to "Babymetal Apocalypse Web" members in December 2014 announced the transition to a new official fanclub called "The One", which started with limited edition releases for Live at Budokan: Red Night & Black Night Apocalypse,[206] and would continue to release member-exclusive media with news published to the official fansite.

"[214] Reiko Yukawa, a well-known music critic in Japan, stated, "Babymetal is pretty cute with singing and dancing, they have charisma like Himiko, and glittering that no one can replace.

's Naomiyuki Umezawa felt that Babymetal "stares metal in the face" and "creates extremely precise sounds which attracts fans and requires admiration".

[219] The Daily Dot wrote, "for those of us whose musical tastes fall somewhere in the middle, Babymetal is kind of like a magical, leather-clad, fire-breathing, sonic unicorn.

moment in the middle of the night and realised that Japanese audiences were certain to unquestioningly embrace such a seemingly incongruous mish-mash of cutting-edge musical ideas.

"[226] Rob Zombie, in response to divisive comments from his fans after posting a photo of him posing with Babymetal, said "these three girls had more energy than 90 percent of the bands we play with".