全世界共通リズム感テスト (Worldwide Common Rhythm Sense Test) is an April Fools' Day parody song that first appeared in maimai ORANGE PLUS in April 2015. The song is a meta-joke from the very first detail: the "artist" credit reads ☆リズムに合わせてボタンを叩き達成率を競うゲームです☆, literally "a game where you hit buttons to the rhythm and compete for achievement rate," which is a description of maimai itself rather than a real musician. There is no melody, no vocal track, no song in the conventional sense, just a steady 120 BPM beat with a single chime at the end. The joke extends to the chart design. The Expert chart (Level 10) consists of 129 notes that are all Break notes, the strictest judgment type in the game, placed at uniform quarter-note intervals, leaving no room for timing error. The Master chart (Level 12) is identical in layout but forces two additional modifiers: the game's sound effects are disabled, and the notes themselves are invisible. With both audio and visual cues stripped away, the chart becomes functionally unplayable without external reference or memorization. Both higher-difficulty charts list their notes designer as "(無し)", "none", reinforcing the gag that no real design work went into these anti-charts. Originally available for only one week (April 1–7, 2015) on ORANGE PLUS, the song later returned as an 宴 (Party / Utage) mode chart set in maimai FiNALE. It was subsequently re-released on maimai でらっくす International.ver (starting with Splash) and remains playable there, though it has never been added to the Japanese arcade version. The Basic (Level 6) and Advanced (Level 8) charts are straightforward single-button-press exercises, serving as a setup for the punchline that awaits on higher difficulties.