Nils Nielsen
A major character in the Gundam Build Fighters series. At just 13 years old, Nils Nielsen is a prodigy known as the Early Genius who has earned three doctoral degrees. Born to a detective father and a martial artist mother, he represents the United States in the 7th Gunpla Battle World Championship. Initially entering the competition solely to investigate the scientific mystery of Plavsky Particles, his fierce battle against Sei Iori and Reiji awakens a genuine passion for Gunpla. He later marries Caroline Yajima, taking her surname, and becomes the technical director at Yajima Engineering.
Overview
A major character in the Gundam Build Fighters series. At just 13 years old, Nils Nielsen is a prodigy known as the Early Genius who has earned three doctoral degrees. Born to a detective father and a martial artist mother, he represents the United States in the 7th Gunpla Battle World Championship. Initially entering the competition solely to investigate the scientific mystery of Plavsky Particles, his fierce battle against Sei Iori and Reiji awakens a genuine passion for Gunpla. He later marries Caroline Yajima, taking her surname, and becomes the technical director at Yajima Engineering.
Appearance
Nils is a young boy with black hair and brown eyes. He frequently wears traditional Japanese clothing consisting of a haori jacket and a blue hakama. When undertaking covert investigations into tournament organizers, he also dons a traditional black ninja outfit.
Personality
Highly analytical and pragmatic, Nils initially views Gunpla Battle with cold logic, treating it purely as a means for scientific research rather than a game to enjoy. He exhibits a passive side when dealing with the assertive Caroline Yajima, often finding himself dragged along by her strong momentum. However, after clashing with passionate rivals, he learns to appreciate the emotional thrill of the sport, developing genuine warmth and camaraderie toward fellow fighters.
Abilities
Possessing extraordinary intelligence that earned him three doctorates at a young age, Nils excels in physics and particle research. Despite having only three months of Gunpla experience, he demonstrates remarkable building and piloting skills, crafting a custom Hyaku Shiki, the Sengoku Astray Gundam, and later the Ninpulse Gundam. Trained in Japanese martial arts by his mother, he utilizes advanced techniques such as Particle Fa Jin, channeling particle energy to shatter opposing Gunpla from within. Later in life, he successfully synthesizes artificial Plavsky Particles and engineers next-generation battle systems.
Background
After gaining international recognition as a prodigy, Nils entered the American qualifiers for the 7th Gunpla Battle World Championship to unlock the secrets of Plavsky Particles. Defeating former champion Greco Logan, he advanced to the World Tournament. During the event, he investigated the mysteries surrounding Sei Iori and Reiji, but after a hard-fought quarterfinals match against them, he realized he had fallen in love with Gunpla Battle itself. Following the resolution of the battle system crisis, he successfully created artificial Plavsky Particles under Yajima Trading's sponsorship, rescuing the sport. He later married Caroline Yajima, changing his name to Nils Yajima, and led system development and young talent training at Nielsen Labs.
Relationships
Caroline Yajima began as the daughter of his corporate sponsor, but her persistent affection eventually led to their engagement and marriage, with Nils taking her family surname. He initially approached Sei Iori and Reiji out of scientific curiosity, but their intense tournament battle forged a lasting friendship and mutual respect. He also shares a respectful bond with Greco Logan, whom he defeated in the US qualifiers and later entrusted with his competitive hopes upon retiring as an active fighter.
Trivia
Nils is widely known by his epithet Early Genius. He chose not to participate in the 8th World Tournament, reasoning that competing with intimate knowledge of particle physics would be unfair to other fighters. In the crossover mobile game Super Robot Wars X-Omega, a collaboration event gave him a unique setting as a native of the Battle Spirits Brave universe, serving as a homage to his shared voice actor across the franchises.
