The story is set in the near future when GunPla Battles, competitions that pit Gundam plastic models against each other, have become popular worldwide in the "Second GunPla Boom." Sei Iori, a first-year middle-school student and the only son of a model shop owner, is talented at building GunPla, but inexperienced in the GunPla Battles. He encounters a mysterious boy named Reiji, who happens to be an accomplished Gundam Fighter. Together, they strive for the GunPla Battle world championships.

[Source: Anime News Network]

Short specials included in the Blu-ray Box 1 & 2 of Gundam Build Fighters.

Episode 1: SD Kishi Fighters First Half
Episode 2: SD Kishi Fighters Second Half
Episode 3: A Letter

[Source: MyAnimeList]

The story takes place seven years after Sei Iori and Reiji won the seventh Gunpla Battle World Tournament. Since then, the rules of Gunpla have been renewed, and the popularity of the sport becomes even more popular. However, one academy is left behind in this change, and that was Seiho Academy, which Sei Iori once attended. The only member of the Gunpla Battle club remaining is Fumina Hoshino, and her alone. In the state the club is in, she is not even able to participate in the preliminaries for Japan's national Gunpla tournament.

In front of her, a single transfer student named Sekai Kamiki appears, a boy who has been training with his master in martial arts. Along with him and the young Gunpla builder Yūma Yūsaka, Fumina forms a new team.

[Source: Anime News Network]

This is a dynamic dream battle featuring many types of Gunpla skirmishing in all sorts of situations by short film.

There are Gunpla battles for every fan in here!

[Source: GUNDAM.INFO]

It has been three years since the end of the Gundam Build Fighters TV series.

Now a totally new story starring Sei Iori and friends is set to begin. It features spectacular Gunpla battles featuring both your favorite mobile suits from the TV series, and all new designs created specifically for GM’s Counterattack.

[Source: GUNDAM.INFO]

The Gunpla Force Battle Tournament is a big event held in GBN once per year. Competing in the final round are Avalon, led by the champion Kyoya Kujo, and the elite 7th Panzer Division led by the cunning Rommel. Starting with Kyoya's Gundam AGE II Magnum, a variety of Gunpla take to the field to determine which is the strongest force!

[Source: Official site]

The Gunpla Force Battle Tournament is a big event held in GBN once per year. Competing in the final round are Avalon, led by the champion Kyoya Kujo, and the elite 7th Panzer Division led by the cunning Rommel. Starting with Kyoya's Gundam AGE II Magnum, a variety of Gunpla take to the field to determine which is the strongest force!

It's the highlight of GBN’s anniversary event, the “Gunpla Battle One-Day Battle Royal”! Participants are selected from the Divers who played most passionately this season, and they're fighting in machines randomly assigned mainly from those Gunpla ranked highest by all Divers in the Great Gunpla Ballot! Now the final round is about to begin, with the tough fighters who've won their respective blocks! There, an unpredictable, super special, never-seen-before Gunpla dream battle will… START!!!

[Source: GundamInfo; emended]

A new Internet service has been born in the world of Gunpla. Within the Metaverse realm, the user can control their own avatar, interact with other users, play Gunpla Battle, and purchase actual Gunpla. Rio Hojo is a boy who has dived into this new world. Studying Gunpla building techniques in the real world with Seria Urutuski, and absorbing Gunpla Battle know-how from Mask Lady in the Metaverse world, he has been honing his skills day by day. After completing his own original Gunpla, the Lah Gundam, Rio happens to encounter some past champions of Gunpla Battle in the Metaverse realm.

[Source: official English website]