Why a pung needs exactly three matching tiles
In mahjong, a pung is a meld—a declared group of tiles—made from three copies of the same tile. “Same” means the same face, not merely the same suit or number: three 5-bamboo tiles match, but a 5-bamboo, 5-dot, and 5-character do not. Honors such as winds and dragons can also form pungs when all three tiles are identical.
The rule distinguishes a pung from other common groups. Two matching tiles make a pair, while three consecutive numbers in the same suit make a sequence, not a pung. A pung is about matching copies, regardless of whether the tile is numbered or an honor.
What happens when you claim a discard
If another player discards a tile that matches two in your hand, you can call for it and lay the three tiles together as an exposed pung. The discarded tile supplies the third copy; you cannot declare a pung with only the two tiles you already hold. Nor can a merely similar tile complete the set: its face must match exactly.
Claiming the discard changes the flow of play. In common rules, the claim takes precedence over the normal turn order: the player who calls the pung takes the discard, exposes the set, then discards a tile. That makes the declaration a tradeoff—you secure a useful group immediately, but reveal part of your hand and give up the chance to keep it concealed. The three matching tiles are therefore not just a pattern; they are the visible proof that makes the claim valid.
