FANTASY ZONE OPA-OPA! -GMT remix- (ファンタジーゾーン OPA-OPA! -GMT remix-) was created as the opening volley of the Game Music Triangle (GMT) collaboration, a cross-company initiative that brought together SEGA's maimai, TAITO's Groove Coaster, and Bandai Namco's Taiko no Tatsujin. For this landmark crossover, SEGA composer Hiroshi Kawaguchi, credited simply as Hiro, revisited the music of his own 1986 arcade classic Fantasy Zone, delivering a self-remix that preserves the original's bright samba character while retrofitting it for the rhythm-game arcade floor. The track mashes two Fantasy Zone compositions into one: the stage theme OPA-OPA! (named after the player's sentient ship) and the cheerful SHOPPING interlude that appears mid-track as a playful detour. Kawaguchi raised the tempo from the original to 142 BPM using digital audio tools, then cut and rearranged the source recording to create phrasing that suits a rhythm-game beat map. Rather than recording a completely new arrangement, he deliberately kept the original FM-synth bass and lead lines intact, layering a punchier modern rhythm section underneath. Throughout the song, authentic Fantasy Zone arcade sound effects, credit chimes, shot noises, and miss tones pulled straight from the PCB, are sprinkled in as decorative accents, turning the track into a nostalgic audio collage for fans of SEGA's golden age. In the maimai GreeN PLUS era, this was one of the higher-tier offerings: the Master chart (designed by mai-Star) sits at difficulty level 13 with a constant of 13.4, while Jack's Expert chart weighs in at level 10+. The song has since undergone several level revisions across subsequent maimai versions, and its in-game genre shifted from the original COLLABO label to GAME & VARIETY, where it has remained.