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Claiming the last discarded tile for a melded kong is done by clearly calling “kong” or “kan”, placing the tile face-up along with the three matching tiles from the hand. After revealing a new kan dora, the player takes a replacement tile from the dead wall and continues his turn as if he’d drawn a tile from the wall.
The dead wall always comprises 14 tiles, so after a kong the dead wall is replenished with the last tile of the wall.

Claiming the last discarded tile for a pung is done by clearly calling “pung” or “pon” and placing the tile face-up along with the two matching tiles from the hand.

A tile can only be claimed for a chow from the player on the left. Claiming the last discarded tile for a chow is done by clearly calling “chow” or “chi”, placing the tile face-up along with the two tiles from the hand that complete the set.

Tiles in melded sets can not be rearranged to form other sets, and they cannot be discarded.
After calling a tile, the relevant tiles from the hand are immediately exposed. It is allowed to make the discard before the claimed tile is taken. If the claimed tile is not taken within the next two opponents’ turns, i.e. before another two discards has been made, the player has a dead hand.



Melded sets are placed to the right of the players tiles in clear view for all players. Claimed tiles are rotated to indicate which player made the discard. If the tile was discarded by the player sitting on the left, the claimed tile is put on the left side of the set. If the tile was discarded by the player sitting in front, the claimed tile is put in the middle of the set. If the tile was discarded by the player sitting on the right, the claimed tile is put on the right side of the set. A claimed kong has one rotated tile. A kong made by extending an open pung has two rotated tiles: the extending tile is placed by the previously rotated tile.
   

A player who feeds the third dragon pung/kong to an opponent with two melded dragon pungs/kongs or the fourth wind pung/kong to an opponent with three melded pungs/ kongs of winds must pay the full value of the hand in case Big Three Dragons or Big Four Winds are made on a self-draw (the two remaining opponents pay nothing). In case another opponent feeds the Big Three Dragons or Big Four Winds, he shares the payment equally with the player who fed the third dragon pung/kong or the fourth wind pung/kong.

A melded pung may be extended to a melded kong in a player’s turn after the player has taken a tile from the wall or a replacement tile, i.e. not in a turn where a tile was claimed for chow or pung. The player must call “kong” or “kan” clearly, place the fourth tile by the rotated tile of the pung, allow 3 seconds for mahjong declarations and then reveal a kan dora and take a replacement tile. The dead wall is replenished with the last tile of the wall.

A concealed kong may be declared in a player’s turn after the player has taken a tile from the wall or a replacement tile, i.e. not in a turn where a tile was claimed for chow or pung. The player must call “kong” or “kan” clearly, reveal the four tiles of the kong, then turn the two middle tiles face-down, reveal a kan dora and take a replacement tile. The dead wall is replenished with the last tile of the wall.
A player still has a concealed hand after declaring a concealed kong, if the player has no open sets.
A concealed kong cannot be robbed, except to win on Thirteen Orphans.
Note that four identical tiles only make up a kong, if a concealed kong is declared.