Latent Kingdom is a maimai original instrumental track born from a collaboration between two prominent figures in the Japanese hardcore and rhythm-game music scene: Laur and Kanon Oguni (大国奏音). Released on October 6, 2023 as part of maimai でらっくす BUDDiES, the song was created to commemorate HARDCORE TANO*C's 20th anniversary, a milestone for the influential doujin and dance-music label. True to the collaborative billing, the title itself weaves the composers' initials together: the "L" and "K" in Latent Kingdom stand for Laur and Kanon Oguni respectively, a naming motif Laur has employed in other partnership works. At the time of its debut, the MASTER chart commanded attention with 1,371 total notes, the highest note count of any standard (non-宴会場) chart in maimai DX at release, a record it held until surpassed by 系ぎて in February 2024. The MASTER chart, designed by Safata.GHz and rated 14+ (constant 14.9), is characterized by relentless density, heavy Break-note usage on top of an already demanding Tap count, and patterns that test both endurance and split-second precision. The EXPERT chart (12+, constant 12.8), designed by Luxizhel, offers a still-formidable challenge with 782 notes. Latent Kingdom was initially locked behind a boss-fight gate in the Friend Matching system, players had to reach SSS1 class and defeat a special boss friend to earn it. This barrier was progressively relaxed across several updates before the song became generally available by default in BUDDiES PLUS (March 2024). Musically, Latent Kingdom is a driving hardcore instrumental at 201 BPM, featuring violin performances by both Laur and Kanon Oguni. The music video and jacket art, created by yoshimo, depict the two composers. A long version later appeared on Laur's fourth album, The Abyss of Despair, and was also included on the maimai でらっくす ベストアルバムちほー3 soundtrack. The track was additionally ported to CHUNITHM LUMINOUS PLUS from August 2024 onward and was selected as one of the online preliminary challenge songs for KING of Performai The 6th, SEGA's competitive rhythm-game tournament series.