Shoot-em-up games have not been a big part of Game Center CX. Star Force was a brief challenge in season 1, and Twinbee was a DVD-only episode, but nothing else has garnered attention. They’re difficult, sure, but generally short. Like RPGs, they’re a type of game that probably wouldn’t make a great episode.
But for whatever reason, this challenge is Super Fantasy Zone, the Mega Drive/Genesis sequel to Sega’s arcade hit. Honestly, though, it’s definitely the exception and not the rule — Fantasy Zone games are similar to Defender: each level a long, two-way-scrolling zoetrope where you simply have to destroy all the enemy pods while avoiding the little ones.