Gamehelpriichimahjong

= Kurzbeschreibung = äöü

Japanesisches Mahjong wird über mehrere Hände hinweg gespielt. In jeder Hand ist es das Ziel, durch das Ziehen und Ausrufen von Steinen zu einer gültige Mahjong-Hand zu gelangen. Die Steine (oft auch als Ziegel bezeichnet) bestehen aus drei Standardfarben (Zahl, Bambus, Kreis) und zwei Sonderfarben (Drachen und Winde, im Englischen als "honor tiles" bezeichnet). In den Standardfarben gibt es 4x9 Steinen mit den Zahlwerten 1-9, während es 4x4 Windsteine (alle Himmelsrichtungen) und 4x3 Drachensteine (rot, grün, weiss) gibt. Die Gesamtzahl der Steine ist somit 136. Die Sitzplätze der Spieler sind mit je einer der vier Windrichtungen markiert und rotieren nach speziellen Regeln, während das Spiel über mehrere Hände hinweg fortschreitet.

Eine gültige Mahjong-Hand besteht in der Regel aus 4 Sets zu je drei Steinen und einem Paar gleicher Steine. Die Sets können entweder Sequenzen, im folgenden als Strassen bezeichnet, von drei Steinen in der selben Standardfarbe sein, oder aber Drillinge oder Vierlinge identischer Steine sein. Zu dieser Grundkomposition gibt es zwei wesentliche Ausnahmen (siehe unten). Die Sets können durch das Ziehen von Steinen vervollständigt werden (die Zugreihenfolge ist gegen den Uhrzeigersinn) oder aber durch das Ausrufen von Steinen, die von anderen Parteien abgelegt wurden. Im letzten Fall wird ein offenes Set gebildet d. Sequences can be only be called from discards made by the player to the left. Unless quadruplets occur, a hand consists of 14 (3x4 + 2) tiles and players discard down to 13. For every quadruplet, a replacement tile is drawn.

Japanese Mahjong is particular in that each valid hand must also fulfill at least one scoring condition (Yaku). These Yaku are properties of hands, and the most important ones are listed below. Different Yaku are worth different numbers of big points (Han). Secondly, the game is particular because some of the tiles (at random) are used up as so-called Dora indicators. The indicators identify tiles that will add Han to a hand, specifically the one that is next in sequence. More Dora tiles become available through forming quadruplets and through Riichi bets.

The calls for completed melds are Chi/Chii/Chow (sequence), Pon/Pong/Pung (triplet), and Kan/Kang/Kong (quadruplet). The calls to complete a winning hand are Tsumo if it is a drawn tile and Ron if it is a discarded tile. A pair can only be completed from a called tile if the call is Ron. A tile that does not complete a meld or hand can never be called. Riichi is a special call that indicates that a 1000-point bet is placed. The bet is to complete a hand without altering it from this point on. It is available when the hand misses exactly one tile. The two main benefits of calling Riichi are hidden Dora tiles (also called Ura-Dora) and, most importantly, the fact that a Riichi call is a Yaku in itself.

The final value of a hand is calculated from its Yaku and sets. Unless the hand has many Han, there are also small points (Fu) that are used to compute the score.

Yaku

Some Yaku give variable Han depending on whether a hand relied on any open meld (open hand) or not (closed hand). Note that a meld-free hand completed via Ron is always considered closed, but the specific set is no longer considered concealed. For these variable Yaku, the lower number refers to open hands.

Common call-based Yaku

Riichi (1 Yaku), Ippatsu (completing hand within a single round after calling Riichi, 1 Han)

Common basic Yaku

All simples (no terminal or honor tile in any of the sets, 1 Han), no-points hand (a closed hand free of any additional Fu, 1 Han), fully concealed hand (completing a closed hand via Tsumo, 1 Han)

Common honors-based Yaku

Triplet or quadruplet of round wind, seat wind, or any dragon (1 Han each; if round wind and seat wind coincide, both count)

Common sequence-based Yaku

Identical sequences in all three suits (1 or 2 Han), duplicated sequence in the same suit (1 Han, only for closed hand)

Common terminal-based Yaku

Clean outside hand (all sets involve 1 or 9 tiles of the standard suits, 2 or 3 Han), mixed outside hand (all sets involve 1 or 9 tiles of the standard suits or honor tiles, 1 or 2 Han)

Common triplet-based Yaku

Three concealed triplets (2 Han), all-triplet hand (no sequences, 2 Han), three identical triplets in the standard suits (2 Han)

Common suit-based Yaku

Full flush (all sets from the same standard suit, 5 or 6 Han), half flush (all sets from the same standard suit or honor tiles, 2 or 3 Han)

In addition, there are rarer Yaku including the most valuable hands of them all: Yakuman hands (see below for a full list). There are two exceptions to the general structure of Mahjong hands: the first is a Yaku (2 Han) called 7 pairs, which is always a closed hand consisting of 7 different pairs. The second is a Yakuman hand called 13 orphans that consists of all 13 different terminal (1/9) and honor tiles and an additional tile from the same set of 13 tiles. Naturally, this is also always a closed hand.

Scoring

Exchange of points

If a hand is won by Tsumo, all other players pay the winner. If a hand is won by Ron, only the discarder pays the one or, rarely, more winners. The value depends on both Han and Fu unless the hand has at least 5 Han. The player sitting in the East seat (the dealer) always pays and gains more points. The other three seats are all equivalent in terms of scoring. A single round is completed after the seats have rotated once in full. However, the seats rotate only if the dealer does not win. A hand ends in a draw if no winning hand is declared before the tiles run out. The scoring in a draw is particular and depends on whether hands are declared to be what is called Tenpai (one tile away from being complete) or not. The total sum of points involved is always 3000.

The small points (Fu) are awarded to sets themselves. Sequences are worth nothing. Concealed triplets are always twice as valuable as open ones. Triplets of honor or terminal tiles are twice as valuable as triplets of common suit tiles (2-8). Quadruplets are four times as valuable as the corresponding triplets. Some Fu are given to the pair if it is a relevant wind or dragon. Finally, the base Fu of a hand are 30 (concealed hand winning by Ron), 25 (7 pairs hand), or 20 (all other cases).

Dora tiles

Anytime a quadruplet is formed, a replacement tile is drawn from the dead wall, and a new Dora indicator is revealed. Together with the 4 replacement tiles, the Dora indicators are part of the 14-tile dead wall. One indicator is revealed at the start of each round. Each tile that is next in rank after the indicator in the same suit will count as 1 Han in a winning hand. For the standard suits, 9 wraps back to 1, for the winds, the order is ESWN, wrapping back from N to E. For dragons, the order is by Japanese alphabetical order (chun (red), haku (white), hatsu (green)), wrapping back from green to red. There can never be more than 4 quadruplets formed in a single hand, at which point all 5 Dora indicators in the top row are visible. The ones below are the aforementioned Ura-Dora. They will be revealed only if a player who called Riichi wins a hand. This means that a maximum of 10 types of tiles could be Dora tiles. As a result, the call to form a quadruplets must be made with care.

Strategy

Hand building

Generally speaking, Mahjong allows only drawing, discarding, and calling tiles, which means that the basic options are not complex. In Japanese Mahjong, it is frequently beneficial to keep the hand closed, that is, to refrain from forming melds through calling tiles. Because of the one-Yaku requirement, indiscriminate tile calls can easily lead to a hand that is virtually impossible to rescue. In particular, calls for sequences involving terminal tiles should be evaluated carefully. The reason is that the three simplest and most common Yaku, Riichi, all-simples, and the no-points hand, all become impossible by such a call. Building toward specific, rarer hands usually makes sense only if the hand drawn initially is well on its way towards completion. In these cases, tile calls are often essential to have a realistic chance.

Defensive play

Players begin to get an idea of the hands of other players through two main mechanisms: open melds and discarded tiles. The discarded tiles are visible for everyone and remain associated with each player. On average, the safest tiles to discard are wind tiles that are neither seat nor round wind. All honors tiles have the advantage that they play very limited roles, so the discard tableaus will give good hints if, for example, a particular dragon tile is safe to discard. In the standard suits, terminal tiles are, on average, safer to discard than central tiles because they can complete fewer sequences and because they need to be avoided for several Yaku. Later in a hand, the hopes to complete one's own hand might be so small that the priority becomes to avoid discarding tiles that lead to a Ron call. In a bad hand, it might be worthwhile to discard dangerous tiles early and hold on to safer tiles. Avoiding discards that complete hands is nearly as important as winning hands in Japanese Mahjong.

Furiten

The discard tableau plays another important role: a tile that would complete a player's hand found among the discards means that that player is in a state called Furiten. In this state, the player cannot win a hand by Ron. This rule has the very useful consequence that discarding a tile that is found in someone else's discards is always a safe defensive play against that player. Similarly, the rule means that it is unwise to change frequently the sets targeted for one's own hand. In doing so, the discard tableau will inevitably fill up with many different and unrelated tiles, which increases the chance of being Furiten and makes it easier for other players to discard tiles.

BGA implementation

User interface

Players can discard tiles, when it is their turn, by clicking on them. There is a player preference to turn on a confirmation button that can be useful when playing on small screens. Other options on a player's turn are buttons to form a "secret" quadruplet or an appended quadruplet. The former keeps the hand closed and is counted as a concealed set even though it is visible to other players. Finally, if the drawn tile completes a winning hand, the Tsumo button will be available. Use it to declare a win. The best scoring hand in terms of Han has to be selected according to the rules, and this is done automatically. Players do not have to denote or score hands on their own.

Whenever you discard a tile and you still have a closed hand and have not called Riichi yet, you can check the box next to Riichi close to your name and seat information. In real life, a Riichi call is done accompanying the discard and, to emphasize this, a notification is sent immediately to all players. Importantly, this only applies to a valid declaration. An invalid declaration occurs when the resultant hand is not actually one tile away from a winning hand (not in Tenpai yet). In this case, the attempted declaration will be invisible to other players and only you get a corresponding notification. Some valid Riichi calls can lead to a dead hand if the winning tiles are all used up already. This is something players have to monitor themselves. On other players' discarded tiles, buttons for tile calls or declaring a win via Ron will appear automatically. You never click directly on a discarded tile. The tile calls (Pon for a triplet, Kan for a quadruplet, and Chi for sequences) are clarified as needed in the button text itself. Passing on a Ron call puts the player at least temporarily in Furiten (permanent if Riichi was called prior).

If a game ends in an exhaustive draw, buttons appear to declare a Tenpai (hand one tile way) or Noten (anything else) hand. Sometimes both calls are eligible, and it is very rarely useful to not call Tenpai in this situation. The only downside of the call is that the hand is revealed to all players.

Tooltips explain the Dora indicators, the piles of remaining tiles (wall tiles), the bonus counter and Riichi bets on the table, as well as open tiles. The tile set itself can be changed via player preference. The "abstract" set is an original design meant to be readable universally. When a player is in the state of Furiten due to discarded tiles, the font used for the player name on the main game screen changes to highlight this. In this case, the Ron button will not show up even though the discarded tile would complete a winning hand (this is the definition of Furiten: not being able to win on a discarded tile).

Timing and automation

When setting up a table, it is possible to select options that let available calls time out. This is only available for real-time games not including training mode. It is the recommended mode in this case as it mimics what happens at a live table. Alternatively or additionally, every player has the option to set a preference to pass on some calls automatically. Note that it is generally visible to other players when this happens due to BGA's clock management, which means that it can reveal information about a hand. These options are meant primarily to facilitate turn-based play. You should understand that turning on such automation options might irritate other players. This is because the gain in information might to lead to situational advantages or disadvantages amongst your opponents.

Rule variants

Japanese Mahjong is a traditional game played in countless variants and house rules. While competition rules are increasingly standardized, the implementation offers two common variants: first, some of the 5-tiles in the standard suits can be marked red. These tiles count as Dora tiles and add one Han to the hand's value independent of and cumulative with the visible Dora indicators. Like all Dora tiles, they do not constitute a Yaku in itself. Second, so-called abortive draws can be allowed. These are special conditions upon which a hand is aborted, and new tiles are dealt. The five types are the following: three Ron calls on the same tile; fourth quadruplet formed unless they are all by the same player; four Riichi calls; four of the same wind tile discarded without interruption to start the hand; calling an aborted hand when the dealt tiles include at least 9 unique terminal or honor tiles. The last one is the only abortive draw involving player choice.

In addition, the game length can be set. Just playing the East round means that the seats need to rotate in full once. A second full rotation would be the South round. The game can end earlier if the option is selected that negative points are not allowed. In this case, the game will end immediately if a player drops below zero points. It can also last longer if the option is set that ties (for the win) must be broken. In this case, extra hands are added.

Finally, the starting points can be adjusted (20K, 25K, or 30K). This is of relevance only if a player dropping into negative points will actually end the game. If negative points are allowed, the number of starting points is a completely inconsequential choice.

Player preferences

Aside from the tile set and the confirmation button (see above), players can set the aforementioned preference for automated passing and a similar option for automated discarding. Pass options on each player's own discard refer exclusively to Riichi calls. Automatic discard options refer exclusively to hands after Riichi was called. Because player preferences are primarily meant to change the appearance, changing them has no immediate effect despite the page reloading. They come into action only after the next user input has occurred (tile discarded or button press). Players must remember to change them back to the desired state at the beginning of a hand to avoid passing on important calls. The final available player preference is to enable animations. These are implemented for the most common and important game events (drawing tiles, discarding tiles, forming melds like triplets or sequences). These animations help, especially for beginners, in understanding what the general flow of the game is. There are three options (off, fast, slow).