The turtle — sometimes called the dragon — is the layout almost everyone means by mahjong solitaire. It has been standard since the first computer versions in the early 1980s, and its structure has specific consequences for how you should play.
The five layers
The bottom layer is a broad slab of 87 tiles, eight rows deep and up to twelve wide, with three tiles protruding at the sides. On top of it sits a 6×6 block of 36, then a 4×4 of 16, then a 2×2 of 4, and finally one tile at the peak. 144 in total.
Three regions with different characters
- The outer rim — the edges of the bottom layer. Almost always free on one side, rarely blocked, and therefore low priority. These tiles will still be there later.
- The central stack — the tiles under layers two through five. Blocked for most of the game and the source of nearly all dead ends.
- The protruding tiles — one on the left, two on the right. Permanently free. Your emergency reserve.
Why the centre matters most
Thirty-six tiles in the bottom layer sit directly under the 6×6 block. They cannot be touched until that block is substantially cleared, and the block itself cannot be cleared until the layers above it are gone. That is a chain of dependencies four deep.
The consequence: prioritise the peak and the 2×2 immediately, then work down. Every move spent on the outer rim while the central tower stands is a move that does not advance the real problem.
The two-right, one-left asymmetry
The turtle has one protruding tile on the left and two on the right. This is a genuine asymmetry in the classic layout, not a rendering quirk. It means you have three permanently available tiles, which can form at most one pair among themselves — and only if two of them happen to match.
In practice, treat them as three independent spare moves, each of which needs a partner elsewhere.
Clear top-down, not left-to-right
The instinct is to work across the board. The structure rewards working downward: peak, then 2×2, then 4×4, then the 6×6, then the base.
The tiles that strand most often
Two positions cause a disproportionate share of dead ends. The tiles in the middle of the bottom layer, under the centre of the 6×6 block, are the last to become available — if their matches were removed earlier, the board is finished.
And the tiles buried in the middle rows of the 6×6 block itself are blocked on both sides for a long time. When you see two of a face in that block and two free elsewhere, think hard before taking the easy pair.
Other layouts
Layouts vary enormously — pyramids, castles, spiders, letters — and each has its own difficulty profile. What makes the turtle the standard is balance: it has enough free tiles at any moment to keep the game moving, and enough depth to require planning. This board uses the classic turtle for exactly that reason.