One mechanic, two depths. Four rows, a bar falling one row per beat, and every tap a note in the track rather than a click on top of it. Pick the right word with one strike — or, when the rows are syllables, build the word with several.
The count-in never shows the falling bar. If the bar is on screen you may strike; if it isn’t, you can’t — one rule with no exceptions, so there is never a turn to guess about.
Your taps are the instrument. Every hit is a note from the track's pentatonic scale, walking upward as your combo builds — so a streak resolves into a melody and no interval can ever sound wrong. The instrument changes as the mix grows: woodblock, then pluck, then bell, then lead stab. Accuracy changes the timbre, not just the score — perfect hits ring bright and wet, late ones come out choked and dry. A miss doesn't buzz at you; it just leaves a hole where a note should have been.
Still synthesised, because an artifact can't fetch audio. It is built as buses — drums, bass, pads, lead, taps, with reverb and delay sends and the pads sidechained to the kick — so real stems drop straight into the same structure.