華天月兎 (Katengetto) is an original commissioned song (書き下ろし) for maimai でらっくす CiRCLE, composed and arranged by satella with lyrics by the same artist and vocals by Risa Yuzuki. The title combines characters for "splendor" (華), "heaven" (天), "moon" (月), and "rabbit" (兎), evoking the classic East Asian moon-rabbit legend, a motif reflected in the lyrics' imagery of the harvest moon (十五夜お月さん) and purification under moonlight. The song serves as the climactic Perfect Challenge track for Takamagahara Area 2 (高天原ちほー2), unlocked after accumulating 800 km of travel distance. Its narrative context, delivered through the area's flavor text, follows a woman transformed into a vengeful oni by grief over a lost child, a tragedy that freezes the mountain's water source and fills the surroundings with malevolent energy. The characters Nigi and Menou intervene, with Menou channeling the power of the full moon to purify the corrupted spirit and restore peace. The MASTER chart, designed by はっぴー (Happy) at Level 14 with a constant of 14.4, features 888 total notes, a demanding count that places it among the more challenging DX charts of the CiRCLE era. The EXPERT chart, designed by Jack at Level 12 with a constant of 12.5, offers a rigorous intermediate step. At 184 BPM, the brisk arrangement drives satella's signature energetic style, complemented by Risa Yuzuki's clear vocal delivery. 華天月兎 remains exclusive to maimai DX, with no ports to other music games as of its release.