Agari houki

Agari houki 「アガリ放棄」, or a dead hand, is a penalty which prevents the player from winning, making tile calls, or declaring riichi for the rest of the hand. The game otherwise continues as normal. This penalty is given for minor rule violations; it is a less severe version of chombo.

Declaring a tile call, ron/tsumo, or riichi with a dead hand will result in chombo.
For the purposes of exhaustive draws, a dead hand is always considered as not tenpai, because it cannot win.
If the player called riichi before the hand was declared dead, the dead hand penalty applies as normal, and the 1000 points may not be reclaimed. The player must still reveal their hand at exhaustive draw, to prove the hand is tenpai, but the hand is considered "noten" for the purposes of tenpai payments. No chombo is given (unless the hand is actually noten).

Situations

Wrong amount of tiles

At any point of the game, if the player has more or less than 13 tiles (add one after each kan) before drawing the next tile, the hand is considered dead.

Drawing before kamicha discards

Player must not draw his next tile before kamicha discards a tile. Drawing before kamicha discards will result in a dead hand.

Drawing from the dead wall

Accidentally drawing from the dead wall will result in a dead hand.

Kuikae

Main article: Kuikae

Players may call on tiles and discard the exact tile that was called, or discard any tile that would complete the chii after calling chii. This will result in a dead hand if the ruleset forbids so.

Improper tile calls

Players may end up calling on discarded tiles, without having the appropriate tiles to complete a tile group. For example, a player may call "pon" on a tile, without having the prerequisite paired tiles. A player may even declare a winning hand. If the hand is revealed with an improper win, then it is declared a chombo. However, if the hand was not revealed during this situation, then it may be declared as a dead hand instead.

In case a player wins by tsumo but calls "ron" instead (or its reverse), correction is allowed.
In case a player tends to call "chii" on a tile but calls "pon" instead (or other combinations among "chii", "pon" or "kan"), it cannot be corrected and dead hand is declared.

Online platforms

When playing online, players do not need to worry about breaking rules - the game software does not allow illegal plays to occur. No known online platform allows a dead hand case to occur. Therefore, these cases can only occur with real tile play.