Japan Press R, Left, Right, L, Right, R at the title screen. A sound will confirm correct code entry. An option to play Uranoid will now appear on the single player menu.
Geometric backgrounds, metal frame, and Twin Block
Successfully complete the game again on a cleared saved game file in Uranoid, and Quest Game modes to unlock seven geometric backgrounds, a metal frame, and Twin Block.
Successfully complete all levels and save your friends to unlock the Uranoid option at the main menu.
Original Vaus ship
Complete all Quest mode levels.
Successfully complete Zone Z' in Quest mode.
Successfully complete Zone W in Quest mode.
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Successfully complete Zone V in Quest mode.
Successfully complete Zone V' in Quest mode.
Happy Smiling background music
Successfully complete Eta-5 in Uranoid with a score of at least 400,000 points.
Captain Neo background music
Successfully complete Theta-5 in Uranoid with a score of at least 400,000 points.
Revenge Of Arkanoid background music
Successfully complete Iota in Uranoid with a score of at least 400,000 points.
Strategy guides from GameFAQs