Hi-Fi Unicorn is a five-member South Korean-Japanese band that debuted on June 26, 2023, under FNC Entertainment. The group consists of members who won the joint SBS Medianet, TBS, and FNC Entertainment audition program The Idol Band: Boy's Battle. They are Kim Hyunyul as the guitarist, Son Kiyoon on the bass, Um Taemin as the vocalist and guitarist, Fukushima Shuto as a vocalist and Heo Min on the drums. Initially known as 항공모함 (Aircraft Carrier) during the semi-finals, the band was later renamed Hi-Fi Unicorn for the finals, which took place on March 5, 2023. Hi-Fi Unicorn released their debut digital single "Over the Rainbow" on June 26, 2023 followed by the band's second digital single, "U&I," on November 29, 2023, and their third single "ABC is," which dropped on March 2, 2024. On June 4, 2024, Hi-Fi Unicorn released their fourth digital single, "Phantom Pain." The group's first full-length album, Fantasia, was released on August 28, 2024. Prior to the album's release, Hi-Fi Unicorn dropped their fifth digital single, "Left or Right," on July 29, 2024.