"Even in the Quietest Moments" by Supertramp wins this - the backdrop of a constant D in the bass throughout the entire song underlies a shifting palette of major, minor, dominant, and diminished chords, often with 7ths atop them. There's at least seven different chords in the verses and chorus, more if inversions are counted separately. très cool
― Lee626, Saturday, 21 July 2018 03:39 (five years ago) link