Tap any group of two or more matching blocks and they vanish, dropping everything above them into the gap. Clear the board, or as much of it as you can.

It looks like a tapping game and scores like a thinking one. Small clears are always available; big ones have to be built. The blocks that fall into a gap often create a larger group one row down, and a well-chosen clear can cascade halfway across the screen.

The habit worth building: before you tap anything, scan for the clear that will drop the most same-coloured blocks together. Taking easy pairs early breaks up the groups you needed for a chain later — the same reason breaking a completed tube in Magic Sort costs you more than it gains.

Simple enough to play distracted, structured enough to reward attention.