Cascade Rush

The board is six gems wide and five deep. Drag through three or more touching gems of one colour, diagonals included, and release to clear them. A chain is worth its length squared times ten, so a single six-gem chain (360 points) beats two chains of three (180).

Cleared gems fall away and new ones drop in. Whenever the falling stones line up three in a row, they vanish on their own as a cascade, and each cascade in a sequence raises the multiplier. Build a chain of six or more and its last gem becomes a Wild that links with any colour and blasts the eight gems around it when cleared.