Building your side
After the shuffle, each player builds a wall in front of them, two tiles high. With a 144-tile Chinese set each side is 18 stacks long (36 tiles); Japanese 136-tile games use 17 stacks per side, and American 152-tile walls are 19 stacks long. The four walls are pushed together to form a square, often with racks used as straight-edges.
It is customary to build quickly and without looking at faces. If a tile is accidentally exposed, it is turned back over and the wall is reshuffled at that point.
Rolling the dice
The dealer rolls the dice — two or three, depending on the style — and counts around the table, starting with themselves, to decide whose wall will be broken. The number rolled is then counted along that wall to find the exact breaking point. Some styles add a second roll by the chosen player.
The details vary, but the purpose is the same everywhere: nobody, including the dealer, can predict which tiles they will receive. That makes the ritual a simple form of cheating protection.
Breaking the wall
At the break, the wall is split and dealing begins from the tiles just after it, moving clockwise around the square, while play itself moves counter-clockwise. In Chinese and Japanese play, the tiles on the other side of the break form the dead wall, used for replacement tiles after kongs and flowers, and in Japan for dora indicators.
American play has no dead wall in the same sense; replacement tiles after flowers are not drawn because flowers stay in the hand.
When the wall runs out
Play continues until someone wins or the live wall is exhausted. If no one has won when the last available tile is drawn and discarded, the hand is a draw (a wall game). Depending on the style, the deal may stay with the dealer or pass on, and Japanese rules make ready players collect payments from unready ones.
