​Mahjong Stars

In this lesson, we will cover the concept of “open hands”. In previous lessons, we mentioned that you can “call” other players’ discarded tiles. Doing so allows you to complete sequences or triplets in your hand without having the draw those tiles yourself.

 

There are separate calls for when the discarded tile would complete a sequence or when it would complete a triplet. The first call is “chi”, which you can declare when the player on your left discards a tile that would complete a sequence with 2 of the tiles in your hand. The second call is “pon”, which you can declare when any player discards a tile that would complete a triplet with 2 of the tiles in your hand.

 

In either case, when the tile you want to call is discarded, you first declare either “chi” or “pon”. Then, reveal the 2 tiles from your hand which complete the sequence or triplet. Lastly, discard a tile from your hand and take the called tile to complete your turn.

 

The tiles that you use for these calls are placed on your right side. The specific tile that you called from another player is placed sideways with the other 2 tiles. The sideways tile should be placed relative to the other 2 tiles in a way that shows the player from whom you called that tile. For a chi, that means that the tile you called will always be to the left of the other 2 tiles. This will likely cause the sequence to be out of order, but it is important to place them like this (the reason why will be explained in a later lesson!).

 

For a pon, if the tile called was from the player to your right, the sideways tile should be to the right of the other 2 tiles. If it was called from the player across, the sideways tile should be between the other 2 tiles. And just like with a chi, if it was called from the player to your left, it should be to the left of the other 2 tiles.

 

There is also a special call for upgrading a triplet using the fourth matching tile called, “kan”. You can declare “kan” when you have all 4 of the same tile in your hand (closed kan or “ankan”), when another player discards a tile that matches a triplet in your hand (open kan or “daiminkan”), or if you have a tile in your hand that matches a pon that you declared previously (added kan or “shouminkan”). In any of these cases, you upgrade a triplet to a kan.

 

Just like with the previous calls, the kan is placed on your right side. For an ankan, place 2 of the tiles facedown and 2 of the tiles faceup; because you did not call any of the 4 tiles from another player, none of them are placed sideways. For a daiminkan, place the sideways tile in the same way you would for a pon (either of the middle spots is fine if you called from the player across). For a shouminkan, place the added tile sideways above the sideways tile from the pon.

 

For the purposes of completing 4 sets and a pair to win a hand, a kan counts as one of your sets. A kan differs slightly from a triplet when scoring the hand, primarily for yaku that specifically look for multiple kans, all of which will be covered in later lessons.

 

Because a kan uses up 4 tiles in what would usually be considered a set of 3 tiles, you need to draw an extra tile to make up for it. The extra tile comes from the end of the dead wall. The 4 tiles before the dora indicator tile are the “rinshan” or “replacement” tiles. When you declare a kan, you draw 1 of those rinshan tiles, in counter-clockwise order. And because the dead wall must always be 14 tiles, the last tile from the live wall is added to the dead wall when a kan is made. For this reason, you may not declare kan if there are no tiles left in the live wall.

 

Under most rulesets, a kan declaration also means that the number of dora indicator tiles increases. The tile next to the original dora indicator going counter-clockwise is flipped over to act as the next dora indicator. This also increases the number of ura dora indicators for a player who wins after declaring riichi, because they get to reveal the tiles under each dora indicator, including ones created by kan declarations. That makes riichi much more valuable after a player makes a kan.

 

However, making a chi, pon, or daiminkan will cause your hand to become “open”. Your hand is considered open if you have called at least 1 tile from another player’s discards. Conversely, your hand is considered “closed” if you have not called any other players’ tiles in this way.

 

An ankan does not cause your hand to be open, so declaring riichi after an ankan is a powerful move. In some rulesets, you can also declare an ankan after declaring riichi if you happen to draw the last tile that matches a triplet in your hand. However, some rules disallow this under certain conditions (if the kan would change the shape of your hand or your final wait).

 

Making any of these calls, regardless of if they open your hand or not, “interrupts” the current turn. This matters for certain rare yaku and special rules, but the most prominent feature of this “interruption” is the negation of ippatsu. In other words, if any player makes a chi, pon, or kan during the 1 turn after a riichi declaration where ippatsu might be earned, the riichi player loses their chance to gain ippatsu.

 

Here is a video that explains the different types of calls by Light Grunty: