Tap two identical mahjong tiles in turn. If a line of horizontal and vertical segments with at most two turns (three segments) can join them, both are removed.
The line may only pass through empty spaces, including the empty border just outside the board. Remove every tile to finish.
Each tile face appears exactly 4 times (no flower tiles). Every deal is solvable, but removing pairs in the wrong order can still lead to a dead end.
When no pair can be removed, shuffle: the remaining tiles stay in place, their faces are redealt, and the board stays solvable. Hints and shuffles are unlimited but add 10 s and 20 s of penalty time.
Undo is available. Each game lasts up to 60 minutes, and your finishing time includes penalties.