神威 (Kamui) is a high-energy instrumental track by TJ.hangneil, a pseudonym of the prolific Japanese composer sasakure.UK, that originally debuted in the Korean arcade rhythm game EZ2DJ 7thTraX CLASS R -Codename:Violet-. Clocking in at a relentless 210 BPM, the song is driven by blistering synth melodies and aggressive percussion, traits that cemented its reputation as a boss-tier track in every rhythm game it has since appeared in. The title is an ateji (phonetic kanji reading) of the Ainu word kamuy, meaning "god" or "spirit," lending the track a mythic weight that matches its intensity. The song's path into SEGA's rhythm game ecosystem was anything but straightforward. Legal disputes between EZ2DJ's developer and KONAMI had long made crossovers from the series seem impossible for Japanese releases. However, because composers retained copyright for songs contributed to EZ2DJ from its 7th installment onward, SEGA was able to license 神威 directly from sasakure.UK rather than through the original game publisher. This cleared the way for the track to appear first in CHUNITHM AIR PLUS (2017), followed by オンゲキ (2018), and finally maimai でらっくす BUDDiES (2023). In maimai, 神威 initially required clearing a Perfect Challenge within the limited-time TJ.hangneil area, demanding 400 km of cumulative in-game travel before the song could be attempted. It became generally unlockable on March 21, 2024 with the BUDDiES PLUS update. The MASTER chart, designed by ロシェ@ペンギン (Rocher@penguin), features an unusually dense concentration of Touch notes (155) among its roughly 1,260 total notes, a key factor in its classification at Level 14+, upgraded from its original Level 14 shortly after launch. The EXPERT chart, designed by はっぴー (Happy), offers a demanding 12+ experience in its own right with 842 notes.