Shogi

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Shogi
Shogi board pieces and komadai.jpg
A game of shogi (Yagura opening)
Genre(s) Board game
Abstract strategy game
Players 2
Age range 5+
Setup time < 2 minutes
Playing time 30 mins. to 2 hours (typically)
Random chance None
Skill(s) required Strategy, tactics
Synonym(s) Japanese chess
The Generals' Game

Shogi (将棋?, shōgi) (/ˈʃɡ/, Japanese: [ɕo̞ːɡi] or [ɕo̞ːŋi]), also known as Japanese chess or the Generals' Game, is a two-player strategy board game in the same family as Western (international) chess, chaturanga, makruk, shatranj, janggi and xiangqi, and is the most popular of a family of chess variants native to Japan. Shōgi means general's (shō ) board game (gi ).

The earliest predecessor of the game, chaturanga, originated in India in the 6th century. Shogi in its present form was played as early as the 16th century, while a direct ancestor without the drop rule was recorded from 1210 in a historical document Nichūreki, which is an edited copy of Shōchūreki and Kaichūreki from the late Heian period (c. 1120).

Shogi was the earliest chess variant to allow captured pieces to be returned to the board by the capturing player.[1] David Pritchard compares this rule to the practice of 16th century mercenaries switching loyalties when captured.[1]

Equipment[edit]

A traditional shōgi-ban (shogi board) displaying a set of koma (pieces). The pieces on the far side are turned to show their promoted values. The stands on either side are komadai used to hold captured pieces. The board itself is raised for the comfort of players seated on tatami mats (background), and is hollowed underneath to produce a pleasing sound when the pieces are moved.

Two players, Sente 先手 (Black; more literally, person with the first move) and Gote 後手 (White; person with the second move), play on a board composed of rectangles in a grid of 9 ranks (rows) by 9 files (columns). The rectangles are undifferentiated by marking or color. The board is nearly always rectangular; square boards are uncommon. Pairs of dots mark the players' promotion zones.

Each player has a set of 20 wedge-shaped pieces of slightly different sizes. Except for the kings, opposing pieces are undifferentiated by marking or color. Pieces face forward (toward the opponent's side); this shows who controls the piece during play. The pieces from largest (most important) to smallest (least important) are:

Several of these names were chosen to correspond to their rough equivalents in international chess, and not as literal translations of the Japanese names.

Each piece has its name written on its surface in the form of two kanji (Chinese characters used in Japanese), usually in black ink. On the reverse side of each piece, other than the king and gold general, are one or two other characters, in amateur sets often in a different color (usually red); this side is turned face up during play to indicate that the piece has been promoted.

Following is a table of the pieces with their Japanese representations and English equivalents. The abbreviations are used for game notation and often when referring to the pieces in speech in Japanese.

Closeup of shogi pieces. Top: +R, R, K (reigning), K (challenging), B, +B. Bottom: +L, L, +S, S, G, N, +N, P, +P
English name Image Kanji Rōmaji Meaning Abbreviations Betza notation
King
(higher ranked player or reigning champion)
Reigning king 王將 ōshō king general K ō K
King
(lower ranked player or challenger)
Challenging king 玉將 gyokushō jeweled general K gyoku K
Rook Rook 飛車 hisha flying chariot R hi R
Promoted rook
("Dragon")
Promoted rook 龍王 ryūō dragon king +R or 竜* ryū FR
Bishop Bishop 角行 kakugyō angle mover B kaku B
Promoted bishop
("Horse")
Promoted bishop 龍馬 ryūma or ryume dragon horse +B uma WB
Gold general
("Gold")
Gold general 金將 kinshō gold general G kin WfF
Silver general
("Silver")
Silver general 銀將 ginshō silver general S gin FfW
Promoted silver Promoted silver 成銀 narigin promoted silver +S (全) WfF
Knight Knight 桂馬 keima cassia horse N kei ffN
Promoted knight Promoted knight 成桂 narikei promoted cassia +N (圭 or今) WfF
Lance Lance 香車 kyōsha incense chariot L kyō fR
Promoted lance Promoted lance 成香 narikyō promoted incense +L (杏 or 仝) WfF
Pawn Pawn 歩兵 fuhyō foot soldier P fu fW
Promoted pawn
("tokin")
Promoted pawn と金 tokin reaches gold +P と (or个) to WfF

* The kanji is a simplified form of .

An example set of "international" pieces. In this set, those pieces that do not have their equivalents in chess have symbols that iconically show their movement (e.g. the silver general's crown and ribbons point towards its possible directions of movement).
Animal character pieces (Cf. dōbutsu shōgi).

English speakers sometimes refer to promoted bishops as horses and promoted rooks as dragons, after their Japanese names, and generally use the Japanese term tokin for promoted pawns. Silver generals and gold generals are commonly referred to simply as silvers and golds.

The characters inscribed on the reverse sides of the pieces to indicate promotion may be in red ink, and are usually cursive. The characters on the backs of the pieces that promote to gold generals are cursive variants of 'gold', becoming more cursive (more abbreviated) as the value of the original piece decreases. These cursive forms have these equivalents in print: for promoted silver, for promoted knight, for promoted lance, and for promoted pawn (tokin). Another typographic convention has abbreviated versions of the original values, with a reduced number of strokes: for a promoted knight (桂), for a promoted lance (香), and the as above for a promoted silver, but for tokin.

The suggestion that the Japanese characters have deterred Western players from learning shogi has led to "Westernized" or "international" pieces which use iconic symbols instead of characters. Most players soon learn to recognize the characters, however, partially because the traditional pieces are already iconic by size, with more powerful pieces being larger. As a result, Westernized pieces have never become popular. Bilingual pieces with both Japanese characters and English captions have been developed as have pieces with animal cartoons.

Setup and gameplay[edit]

Shogi starting setup; Black (at bottom) moves first.

Each player sets up his pieces facing forward (toward his opponent).

  • In the rank nearest the player:
    • the king is placed in the center file;
    • the two gold generals are placed in files adjacent to the king;
    • the two silver generals are placed adjacent to each gold general;
    • the two knights are placed adjacent to each silver general;
    • the two lances are placed in the corners, adjacent to each knight.
That is, the first rank is
 L   N   S   G   K   G   S   N   L 
or
  • In the second rank, each player places:
    • the bishop in the same file as the left knight;
    • the rook in the same file as the right knight.
  • In the third rank, the nine pawns are placed one per file.

Traditionally, the order of placing the pieces on the board is determined. There are two commonly used orders, the Ōhashi order 大橋流 and the Itō order 伊藤流.[2] Placement sets pieces with multiples (generals, knights, lances) from left to right in all cases, and follows the order:

  1. king
  2. gold generals
  3. silver generals
  4. knights
In ito, the player now places:
5.  pawns (left to right starting from the leftmost file)
6.  lances
7.  bishop
8.  rook
In ohashi, the player now places:
5.  lances
6.  bishop
7.  rook
8.  pawns (starting from center file, then alternating left to right one file at a time)
Deciding who goes first: Furigoma

A furigoma 振り駒 'piece toss' is used to decide who moves first. One of the players tosses five pawns. If the number of tokins (promoted pawns, と) facing up is higher than unpromoted pawns (歩), then the player who tossed the pawns plays gote 後手 'white' (that is, they have the second move).[3] Among amateur tournaments, the higher-ranked player or defending champion also performs the piece toss. In professional games, the furigoma is done on the behalf of the higher-ranked player/champion by the timekeeper who kneels by the side of the higher-ranked player and tosses the pawn pieces onto a silk cloth.[4] In friendly amateur games, a player will ask their opponent to toss the pawns out of politeness. Otherwise, the person who tosses the pawns can be determined by Rock–paper–scissors.[5]

After the piece toss furigoma, the game proceeds. If multiple games are played, then players alternate turns for who goes first in subsequent games. (The terms "Black" and "White" are used to differentiate sides although there is no difference in the color of the pieces.) For each turn, a player may either move a piece that is currently on the board (and potentially promote it, capture an opposing piece, or both) or else drop a piece that has been previously captured onto a square of the board. These options are explained below.

Professional games are timed as in international chess, but professionals are never expected to keep time in their games. Instead a timekeeper is assigned, typically an apprentice professional. Time limits are much longer than in international chess (9 hours a side plus extra time in the prestigious Meijin title match), and in addition byōyomi (literally "second counting") is employed. This means that when the ordinary time has run out, the player will from that point on have a certain amount of time to complete every move (a byōyomi period), typically upwards of one minute. The final ten seconds are counted down, and if the time expires the player to move loses the game immediately. Amateurs often play with electronic clocks that beep out the final ten seconds of a byōyomi period, with a prolonged beep for the last five.

Rules[edit]

Objective[edit]

The game ends when one player captures the opponent's king and the game is won by the capturing player. Thus, the aim of the game is to capture the opponent's king before the opponent manages to do so.

Movement[edit]

Most shogi pieces can move only to an adjacent square. A few may move across the board, and one jumps over intervening pieces.

The lance, bishop, and rook are ranging pieces: They can move any number of squares along a straight line limited only by intervening pieces and the edge of the board. If an opposing piece intervenes, it may be captured by removing it from the board and replacing it with the moving piece. If a friendly piece intervenes, the moving piece must stop short of that square; if the friendly piece is adjacent, the moving piece may not move in that direction at all.

Notation
Steps to an adjacent square
Jumps to a non-adjacent square, bypassing any intervening piece
Ranges along a straight line, crossing any number of empty squares

A king (玉/王) moves one square in any direction, orthogonal or diagonal.

A rook (飛) moves any number of squares in an orthogonal direction.

A bishop (角) moves any number of squares in a diagonal direction. Because they cannot move orthogonally, the players' unpromoted bishops can reach only half the squares of the board, unless one is captured and then dropped.

A gold general (金) moves one square orthogonally, or one square diagonally forward, giving it six possible destinations. It cannot move diagonally backwards.

A silver general (銀) moves one square diagonally, or one square straight forward, giving it five possible destinations. Because an unpromoted silver can retreat more easily than a promoted one, it is common to leave a silver unpromoted at the far side of the board. (See Promotion).

A knight (桂) jumps at an angle intermediate to orthogonal and diagonal, amounting to one square straight forward plus one square diagonally forward, in a single move. Thus the knight has two possible forward destinations. The knight cannot move to the sides or in a backwards direction. The knight is the only piece that ignores intervening pieces on the way to its destination. It is not blocked from moving if the square in front of it is occupied, but neither can it capture a piece on that square. It is often useful to leave a knight unpromoted at the far side of the board. A knight must promote, however, if it reaches either of the two furthest ranks. (See Promotion.)

A lance (香) moves any number of squares directly forward. It cannot move backwards or to the sides. It is often useful to leave a lance unpromoted at the far side of the board. A lance must promote, however, if it reaches the furthest rank. (See Promotion.)

A pawn (歩) moves one square straight forward. It cannot retreat. Unlike international chess pawns, shogi pawns capture the same as they move. A pawn must promote if it arrives at the furthest rank. (See Promotion.) In practice, however, a pawn is usually promoted whenever possible. There are two restrictions on where a pawn may be dropped. (See Drops.)

All pieces but the knight move either horizontally, vertically, or diagonally. These directions cannot be combined in a single move; one direction must be chosen.

Every piece blocks the movement of all other non-jumping pieces through the square it occupies.

If a piece occupies a legal destination for an opposing piece, it may be captured by removing it from the board and replacing it with the opposing piece. The capturing piece may not continue beyond that square on that turn. Shogi pieces capture the same as they move.

Normally when moving a piece, a player snaps it to the board with the ends of the fingers of the same hand. This makes a sudden sound effect, bringing the piece to the attention of the opponent. This is also true for capturing and dropping pieces. On a traditional shogi-ban, the pitch of the snap is deeper, delivering a subtler effect.

Promotion[edit]

A player's
promotion zone (yellow)
△ pieces in hand:
9 8 7 6 5 4 3 2 1  
Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg a
Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg b
Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg Shogi yy22.svg c
                  d
                  e
                  f
g
              h
i
▲ pieces in hand:

A player's promotion zone consists of the furthest one-third of the board – the three ranks occupied by the opponent's pieces at setup. The zone is typically delineated on shogi boards by two inscribed dots. When a piece is moved, if part of the piece's path lies within the promotion zone (that is, if the piece moves into, out of, or wholly within the zone; but not if it is dropped into the zone – see Drops), then the player has the option to promote the piece at the end of the turn. Promotion is indicated by turning the piece over after it moves, revealing the character of the promoted piece.

If a pawn or lance is moved to the furthest rank, or a knight is moved to either of the two furthest ranks, that piece must promote (otherwise, it would have no legal move on subsequent turns). A silver general is never required to promote, and it is often advantageous to keep a silver general unpromoted. (It is easier, for example, to extract an unpromoted silver from behind enemy lines; whereas a promoted silver, with only one line of retreat, can be easily blocked.)

Pieces that promote
△ pieces in hand:
9 8 7 6 5 4 3 2 1  
                  a
                  b
                  c
                  d
                  e
                  f
g
              h
      i
▲ pieces in hand:

Promoting a piece changes the way it moves. The various pieces promote as follows:

  • A silver general, knight, lance, or pawn has its normal power of movement replaced by that of a gold general.
  • A rook or bishop keeps its original movement and gains the power to move one square in any direction (like a king). For a promoted bishop, this means it is able to reach any square on the board, given enough moves.
  • A king or a gold general does not promote; nor can a piece that is already promoted.

When captured, a piece loses its promoted status. Otherwise promotion is permanent.

A promoted rook ("dragon king", 龍王 Ryūō) moves as a rook and as a king. Alternate forms: 龍, 竜.

A promoted bishop ("dragon horse", 龍馬 Ryūma) moves as a bishop and as a king. Alternate form: 馬.

A promoted silver (成銀 narigin) moves the same as a gold general. Alternate forms: 全, cursive 金.

A promoted knight (成桂 narikei) moves the same as a gold general. Alternate forms: 圭, 今, cursive 金.

A promoted lance (成香 narikyō) moves the same as a gold general. Alternate forms: 杏, 仝, cursive 金.

A promoted pawn (と金 tokin) moves the same as a gold general. Alternate forms: と, 个.

Drops[edit]

Traditional piece stands for pieces in hand
Piece stands next to shogi board

Captured pieces are retained in hand and can be brought back into play under the capturing player's control. The Japanese term for piece(s) in hand is either 持ち駒 mochigoma or 手駒 tegoma. On any turn, instead of moving a piece on the board, a player may select a piece in hand and place it – unpromoted side up and facing the opposing side – on any empty square. The piece is then one of that player's active pieces on the board and can be moved accordingly. This is called dropping the piece, or simply, a drop. A drop counts as a complete move.

A drop cannot capture a piece, nor does dropping within the promotion zone result in immediate promotion. Capture and/or promotion may occur normally, however, on subsequent moves of the piece.

A pawn, knight, or lance may not be dropped on the furthest rank, since those pieces would have no legal moves on subsequent turns. For the same reason, a knight may not be dropped on the penultimate (player's 8th) rank.

There are two additional restrictions when dropping pawns:

  1. Two Pawns (Japanese: 二歩 nifu): A pawn cannot be dropped onto a file (column) containing another unpromoted pawn of the same player (promoted pawns do not count). A player with an unpromoted pawn on every file is therefore unable to drop a pawn anywhere. For this reason it is common to sacrifice a pawn in order to gain flexibility for drops.
  2. Drop Pawn Mate (Japanese: 打ち歩詰め uchifuzume): A pawn cannot be dropped to give an immediate checkmate. (Although other pieces may be dropped to give immediate checkmate.) A pawn may, however, be dropped to give immediate check as long as it is not also mate. It is also permissible to mate a king with a pawn that is already on the board.

It is common to keep captured pieces on a wooden stand (駒台 komadai) which is traditionally placed so that its bottom left corner aligns with the bottom right corner of the board from the perspective of each player. It is not permissible to hide pieces from full view.

It is common for players to swap bishops, which oppose each other across the board, early in the game. This leaves each player with a bishop in hand to be dropped later. The ability for drops in shogi give the game tactical richness and complexity. The fact that no piece ever goes entirely out of play accounts for the rarity of draws.


Check and checkmate[edit]

Checkmate by Black
△ pieces in hand:
9 8 7 6 5 4 3 2 1  
                a
                b
                  c
                d
                  e
                  f
                  g
                  h
                  i
▲ pieces in hand:
The most common basic checkmating patterns involve golds

When a player's move threatens to capture the opposing king on the next turn, the move is said to give check to the king; the king is said to be in check. If a player's king is in check, the only way for that player to avoid a defeat is to respond with a move that removes the check (either by moving the king away from the threat, capturing the threatening piece, or placing another piece between the king and the threatening piece). Note, though, that unlike in international chess, there is no official rule that requires a player to defend a king that is being attacked; however, failing to do so is a blunder, as the opponent would then be entirely free to capture it on the next move, thus winning the game.[6]

If the king is in check and there is no possible move which could protect the king, the move is said to give checkmate (tsumi 詰み) to the king. Checkmate effectively means that the opponent is about to win the game, since the king can always be captured on the opponent's next move. Note that a checkmate is not sufficient for a win; the king must be captured on the next move for the opponent to win the game.[6] However, the checkmated player is still allowed to withdraw from the game by resigning (see below).

Winning[edit]

The usual way for shogi games to end is for one side to capture the other side's king. However, there are three other possible ways for a game to end: repetition (千日手 sennichite), impasse (持将棋 jishōgi), and an illegal move (反則手). The first two – repetition and impasse – are particularly uncommon. Illegal moves are also uncommon in professional games although this may not be true with amateur players (especially beginners).

Resignation. The losing player will resign at this point, although in practice play up to the checkmate point rarely occurs, as players normally resign as soon as a loss is deemed inevitable. In traditional tournament play, a formal resignation is required – that is, a checkmate is not a sufficient condition for winning.[7] The resignation is indicated by bowing and/or saying 'I lost' (負けました makemashita) and/or placing the right hand over the piece stands. Placing the hand over the piece stand is a vestige of the older practice of gently dropping one's pieces in hand over the board in order to indicate resignation. In western practice, a handshake may be used.

To announce check in Japanese, one can say ōte (王手). However, this is an influence of international chess and is not required, even as a courtesy.[8] Announcing a check vocally never happens in serious play.

Illegal move[edit]

In professional and serious (tournament) amateur games, a player who makes an illegal move loses immediately. This includes violating the Two Pawns (nifu) and Drop Pawn Mate (uchifuzume) restrictions. The loss stands even if play continued and the move was discovered later in game. However, if neither the opponent nor a third party points out the illegal move and the opponent later resigned, the resignation stands as the result. In friendly amateur games, this rule is sometimes relaxed, and the player is able to take back their move and replay a new legal move.[9][10]

Repetition (draw)[edit]

If the same game position occurs four times with the same player to move, either player loses if his or her moves during the repetition (sennichite) are all checks (perpetual check), otherwise the game is considered a draw. However, in Shogi a draw is not counted for. Players have to restart their game(s) until a winner is declared. This is a significant difference from Western Chess, in which a player can play specifically to obtain draws for gaining points. In Shogi there can be only one victorious through wins. When a draw situation in Shogi occurs, the players have to start a new game in which the players switch colours. The player who was white, becomes black and vice versa. Furthermore, depending on the tournament, players who have reached "sennichite" need to start and play their new game in the remainder of their allowed game time. This rule also contributes to making sennichite a rare occurrence. Repetition draws in Shogi are also rare to achieve, since through the four iterations, every iteration needs contain the same positions. For two positions to be considered the same, even the pieces in hand must be the same as well as the positions on the board. Although rare among professional players, Repetition Draws are even rarer in amateur games.

Pre-1983 sennichite. The rule used to be that it happened if a sequence (and not a position) caused three repetitions. The rule was changed to its current form in May 1983.

Historical sennichite. There was yet another repetition rule used historically by rule codifier Sōko Ōhashi[ja] who was the second Meijin from 1635 until his death in 1654: the player that started a repetition lost the game.[11]

Example[edit]

Repetition Draws have historically been associated with the traditional Double Yagura opening (especially the Complete Yagura formation).[12] However, a surprising Repetition Draw occurred in the endgame of a game between Akira Watanabe (Black) and Yoshiharu Habu on October 3, 2012.[13] The opening was Third File Rook.

After the 121st move (= 61st move in western notation), White (Habu) found himself in a threatmate situation where Black (Watanabe) had a possible 9-move mate sequence of 62. R*8c Gx8c, 63. Sx8c+ Kx8c, 64. R*8b Kx7d, 65. N*6f K-6c (or K-6d), 66. G*5d [mate]. In order to prevent Black's future knight drop (N*6f), White dropped a silver to the 6f square (61. ...S*6f) forcing Black to capture it with his pawn (62. Px6f) leaving the 6f square occupied and unable to accept a knight drop.

After this, White found the Repetition sequence starting with 62. ...G*8i. Dropping the gold to the 8i square puts Black in his own threatmate situation as White is threatening the mate-in-one 63. ...Bx8h+ [mate] on his next move.

Therefore, Black defends the 8h square in the only way he can by dropping a rook to the seventh file (63. R*7h). He cannot remove White's gold with his own gold on 8h (63. Gx8i) since that gold is pinned by White's bishop on 7i.

White, then, trades his golds via the 8h square (63. ... Gx8h). This move is actually forced as Black is threatening to create a 3-move brinkmate sequence via 64. S*8b Gx8b, 65. Nx8b+. And, since White does not have any checkmate sequence available to him, after this, Black will have a mate-in-one with +N8c (or G*8c or R*8c). Thus, White must defend against the brinkmate by creating another threatmate against Black with 63. ...Gx8h. This threatens the 3-move mate sequence: 64. ...Gx7h, 65. K-9h B-8h+ [mate].

Black, of course, must defend against the threatmate by capturing White's gold with his rook (64. Rx8h).

After White's gold is removed, the board position is very similar to the position at after the 123rd move (the first diagram shown above). The only difference is that instead of Black having a gold on the 8h square Black has a rook on 8h. However, this is sufficiently similar to force Black into a Repetition sequence in that Black's rook like the previous gold cannot capture White's bishop on 7i and also is pinned by the same bishop. And, since White still has a gold available to drop, he drops a gold again to the 8i square (64. ...G*8i). This creates another threatmate (threatening again the same mate-in-one ...Bx8h+).

Black must again stop the threatmate by defending the 8h square – this time with a gold (65. G*7h).

Similarly, White captures the rook on 8h with their gold creating the same threatmate as above (65. ...Gx8h). It is here on the 130th move that the Repetition sequence technically starts.

White must again remove the threatmate by capturing White's gold (66. Gx8h).

After these eight moves, we have a near identical position to the position after the 122nd move (62. Px6f). However, there is a small difference in that now White has a rook in hand instead of the two golds and Black has a gold in hand instead of two rooks. Thus, although very similar (and functionally the same in terms of game play), this is not a repetition of the board position at move 122 and why the actual Repetition sequence starts at move 130.

After 66. ...G*8i, 67. G*7h Gx8h, there is a second repeat of the position at move 130. After 68. Gx8h G*8i, 69. G*7h Gx8h, there is a third repetition. And, after 70. Gx8h G*8i, 71. G*7h Gx8h, White makes the fourth repetition leading to a Repetition Draw. After this, a new game was started with Habu playing Black and Watanabe playing White.

Impasse[edit]

The game reaches an Impasse or Deadlock (jishōgi) if both kings have advanced into their respective promotion zones and neither player can hope to mate the other or to gain any further material. An Impasse can result in either a win or a draw. If an Impasse happens, the winner is decided as follows: each player agrees to an Impasse, then each rook or bishop, promoted or not, scores 5 points for the owning player, and all other pieces except kings score 1 point each. A player scoring fewer than 24 points loses. (If neither player has fewer than 24, the game is no contest—a draw.) Jishōgi is considered an outcome in its own right rather than no contest, but there is no practical difference.

As an Impasse needs to be agreed on for the rule to be invoked, a player may refuse to do so if they think that that can win the game in future moves. If that happens, there is no official rule about the verdict of the game.[14]

Amateur resolutions. However, for amateur games there are various guidances. Fairbairn reports a practice (considered a rule by the Shogi Association for The West) where the dispute is resolved by either player moving all their pieces into their opponent's promotion zone and then the game ends with points tallied.[15]

Another resolution is the 27-Point (27点法) rule used for some amateur tournaments.[16] One version of this is simply the player who has 27 or more points is the winner of the Impasse. Another version is a 27-Point Declaration rule. For instance, the Declaration rule on the online shogi site, 81Dojo, is that the player who wants to declare an Impasse win must (i) declare they want to win via Impasse, (ii) their king must be in their promotion zone (in their opponent's camp), (iii) 10 other pieces must be in their promotion zone, (iv) their king is not in check, (v) they have time remaining, and (vi) they must have 28 points if Black or 27 points if White. If all of these conditions are met, then the Impasse declarer will win the game regardless of whether their opponent objects.[17]

Yet another resolution to a refusal to agree to Impasse is the so-called Try Rule (トライルール). In this case, after both kings have entered their corresponding promotion zones, then the player who can move their king to their opponent's king's start square (5a for Black, 5i for White) first will be the winner.[18][19]

Draws in tournaments[edit]

Impasse position of Katoh vs Nakahara 1982
△ pieces in hand: 1227
9 8 7 6 5 4 3 2 1  
              a
              b
                c
            d
                e
        Shogi rah22.svg   f
          g
              h
              i
▲ pieces in hand: 116
Katoh played +N-3f, and Nakahara then agreed to a draw via impasse. Katoh has 29 points, Nakahara 25 points.

In professional tournaments, the rules typically require drawn games to be replayed with sides reversed, possibly with reduced time limits. This is rare compared to chess and xiangqi, occurring at a rate of 1–2% even in amateur games.

The 1982 Meijin title match between Makoto Nakahara and Hifumi Katoh was unusual in this regard with an impasse draw in the first (Double Yagura) game on April 13–14 (only the fifth draw in the then 40-year history of the tournament). This game (with Katoh as Black) lasted for 223 moves with 114 minutes spent pondering a single move. One of the reasons for the length of this game was that White (Nakahara) was very close to falling below the minimum of 24 points required for a draw. Thus, the end of the endgame was strategically about trying to keep White's points above the 24-point threshold.[20] In this match, sennichite occurred in the sixth and eighth games. Thus, this best-of-seven match lasted eight games and took over three months to finish; Black did not lose a single game and the eventual victor was Katoh at 4–3.

Player rank and handicaps[edit]

Amateur players are ranked from 15 kyū to 1 kyū and then from 1 dan to 8 dan. Amateur 8 dan was only honorarily given to famous people. While it's now possible to win amateur 8 dan by actual strength (winning amateur Ryu-oh 3 times), this has yet to be achieved.

Professional players operate with their own scale, from 6 kyū to 3 dan for pro-aspiring players and professional 4 dan to 9 dan for formal professional players.[21] Amateur and professional ranks are offset (with amateur 4 dan being equivalent to professional 6 kyū).[22]

Handicaps[edit]

6-Piece Handicap
△ pieces in hand:
9 8 7 6 5 4 3 2 1  
        a
                  b
c
                  d
                  e
                  f
g
              h
i
▲ pieces in hand:

Shogi has a handicap system (like go) in which games between players of disparate strengths are adjusted so that the stronger player is put in a more disadvantageous position in order to compensate for the difference in playing levels. In a handicap game, one or more of White's pieces are removed from the setup, and instead White plays first.

Notation[edit]

A shogi game record

There are two commons systems used to notate piece movements in shogi game records. One is used in Japanese language texts while a second was created for western players by George Hodges and Glyndon Townhill in the English language.[23][24] Other systems are used to notate shogi board positions.

In western piece movement notation, the format is the piece initial followed by the type of movement and finally the file and rank where the piece moved to. The piece initials are K (King), R (Rook), B (Bishop), G (Gold), S (Silver), N (Knight), L (Lance), and P (Pawn). Simple movement is indicated with -, captures with x, and piece drops with *. The files are indicated with numerals 1–9 while ranks are indicated by letters a–i.Thus, Rx2d indicates 'rook captures on 2d'. Promoted pieces are notated with + prefixed to the piece initial (e.g. +Rx2d). Piece promotion is also indicated with + (e.g. S-2a+) while unpromotion is indicated with = (e.g. S-2a=). Piece ambiguity is resolved by notating which square a piece is moving from (e.g. N6e-5c+ means 'knight from 6e moves to 5c and promotes').

The Japanese notation system uses Japanese characters for pieces and promotion indication and uses Japanese numerals instead of letters for ranks. Movement type aside from drops is not indicated, and the conventions for resolving ambiguity are quite different from the western system. As examples, the western Rx2d would be 2四飛 in Japanese notation, +Rx2d would be 2四龍, S-2a+ 2一銀成, S-2a= 2一銀不成, and N6e-5c+ could be either 5三桂左成 or 5三桂右成 depending on whether the knight moved from the left or right.

Strategy and tactics[edit]

Shogi is similar to chess but has a much larger game tree complexity because of the use of drops greater number of pieces, and larger board size.[25] In comparison, shogi games average about 140 moves per game where as western chess games average about 80 moves per game and minishogi averages about 40 moves per game.[26] Like chess, however, the game can be divided into the opening, middle game and endgame, each requiring a different strategy. The opening consists of arranging one's defenses usually in a castle and positioning for attack, the mid game consists of attempting to break through the opposing defenses while maintaining one's own, and the endgame starts when one side's defenses have been compromised.

Etiquette[edit]

Two men playing shogi outside in Ueno Park, 2014

Shogi players are expected to follow etiquette in addition to rules explicitly described. Commonly accepted etiquette include following:

  • greetings to the opponent both before and after the game
  • avoiding disruptive actions both during the game and after, for instance:
    • not changing the move once realized on the board
    • fair withdrawal without any disruption, such as scattering pieces on the board to demonstrate frustration
  • announcing one's resignation

Shogi piece sets may contain two types of king pieces, (king) and (jewel). In this case, the higher classed player, in either social or genuine shogi player rank, may take the king piece. For example, in titleholder system games, the current titleholder takes the king piece as the higher.

The higher-ranked (or older) player also sits facing the door of the room and is the person who takes the pieces out of their piece box.[4]

Shogi does not have a touch-move rule as in western chess tournament play or chu shogi. However, in professional games, a piece is considered to be moved when the piece has been let go of. In both amateur and professional play, any piece may be touched in order to adjust its centralization within its square (to look tidy).[27]

Taking back moves (待った matta) in professional games is prohibited. However, in friendly amateur games in Japan, it is often permitted.

Professional players are required to follow several ritualistic etiquette prescriptions such as kneeling exactly 15 centimeters from the shogi board, sitting in the formal seiza position, etc.[28]

History[edit]

Boys playing shogi (18th century)
Playing shogi in Japan (ca. 1916–1918)
Human shogi
Kōzō Masuda (升田幸三) in 1952

From The Chess Variant Pages:[1]

The world's first chess variant, chaturanga arose in India in approximately the seventh century AD. From there it migrated both westward and northward, mutating along the way. The western branch became shatranj in Arabia and Orthodox Chess in Europe. The northern branch became xiangqi in China and janggi in Korea. Sometime in the 10th to 12th centuries, 'chess' crossed the channel to Japan where it spawned a number of interesting variants. One of these was called 'Small Shogi'. Eventually, Small Shogi (though it went through many forms) won out over the larger variants and is now referred to simply as 'Shogi'. It is certain that Shogi in its present form was played in Japan as early as the 16th century.

It is not clear when chess was brought to Japan. The earliest generally accepted mention of shogi is Shin Saru Gakuki (新猿楽記?) (1058–1064) by Fujiwara Akihira. The oldest archaeological evidence is a group of 16 shogi pieces excavated from the grounds of Kōfuku-ji in Nara Prefecture. As it was physically associated with a wooden tablet written on in the sixth year of Tenki (1058), the pieces are thought to date from that period. These simple pieces were cut from a writing plaque in the same five-sided shape as modern pieces, with the names of the pieces written on them.

The dictionary of common folk culture, Nichūreki (二中歴?) (c. 1210–1221), a collection based on the two works Shōchūreki (掌中歴?) and Kaichūreki (懐中歴?), describes two forms of shogi, large (dai) shogi and small (shō) shogi. These are now called Heian shogi (or Heian small shogi) and Heian dai shogi. Heian small shogi is the version on which modern shogi is based, but the Nichūreki states that one wins if one's opponent is reduced to a single king, indicating that drops had not yet been introduced. According to Kōji Shimizu, chief researcher at the Archaeological Institute of Kashihara, Nara Prefecture, the names of the Heian shogi pieces keep those of chaturanga (general, elephant, horse, chariot and soldier), and add to them the five treasures of Buddhism (jade, gold, silver, katsura tree, and incense).

Around the 13th century the game of dai shogi developed, created by increasing the number of pieces in Heian shogi, as was sho shogi, which added the rook, bishop, and drunken elephant from dai shogi to Heian shogi. Around the 15th century, the rules of dai shogi were simplified, creating the game of chu shogi in a form close to the modern game. It is thought that the rules of standard shogi were fixed in the 16th century, when the drunken elephant was removed from the set of pieces. There is no clear record of when drops were introduced, however.

In the Edo period, shogi variants were greatly expanded: tenjiku shogi, dai dai shogi, maka dai dai shogi, tai shogi, and taikyoku shogi were all invented. It is thought that these were played to only a very limited extent, however. Both standard shogi and Go were promoted by the Tokugawa shogunate. In 1612, the shogunate passed a law giving endowments to top shogi players (Meijin (名人?)). During the reign of the eighth shogun, Tokugawa Yoshimune, castle shogi tournaments were held once a year on the 17th day of Kannazuki, corresponding to November 17, which is Shogi Day on the modern calendar.

The title of meijin became hereditary in the Ōhashi and Itō families until the fall of the shogunate, when it came to be passed by recommendation. Today the title is used for the winner of the Meijin-sen competition, the first modern title match. From around 1899, newspapers began to publish records of shogi matches, and high-ranking players formed alliances with the aim of having their games published. In 1909, the Shogi Association (将棋同盟社?) was formed, and in 1924, the Tokyo Shogi Association (東京将棋連盟?) was formed. This was an early incarnation of the modern Japan Shogi Association (日本将棋連盟?, nihon shōgi renmei), or JSA, and 1924 is considered by the JSA to be the date it was founded.[29]

In 1935, meijin Kinjirō Sekine stepped down, and the rank of meijin came to be awarded to the winner of a Meijin title match (名人戦?, meijin-sen). Yoshio Kimura (木村義雄?) became the first Meijin under this system in 1937. This was the start of the shogi title matches (see titleholder system). After the war other tournaments were promoted to title matches, culminating with the Ryūō title match (竜王戦?, ryūō-sen) in 1988 for the modern line-up of seven. About 200 professional shogi players compete. Each year, the title holder defends the title against a challenger chosen from knockout or round matches.

After the Second World War, SCAP (occupational government mainly led by US) tried to eliminate all "feudal" factors from Japanese society and shogi was included in the possible list of items to be banned along with Bushido (philosophy of samurai) and other things. The reason for banning shogi for SCAP was its exceptional character as a board game seen in the usage of captured pieces. SCAP insisted that this could lead to the idea of prisoner abuse. But Kozo Masuda, then one of the top professional shogi players, when summoned to the SCAP headquarters for an investigation, criticized such understanding of shogi and insisted that it is not shogi but western chess that potentially contains the idea of prisoner abuse because it just kills the pieces of the opponent while shogi is rather democratic for giving prisoners the chance to get back into the game. Masuda also said that chess contradicts the ideal of gender equality in western society because the king shields itself behind the queen and runs away. Masuda’s assertion is said to have eventually led to the exemption of shogi from the list of items to be banned.[30]

The closest cousin of shogi in the chaturanga family is makruk of Thailand. Not only the similarity in distribution and movements of the pieces but also the names of shogi pieces suggest intimacy between shogi and makruk by its Buddhist symbolism (gold, silver, Cassia and Incense),[dubious ] which is not recognized in Chinese chess at all. In fact, Chinese chess and its East Asian variants are far remoter relatives than makruk. Though some early variants of chaturanga more similar to shogi and makruk are known to have been played in Tang dynasty China, they are thought to have been extinguished in Song dynasty China and in East Asia except in Japan probably owing to the popularity of Chinese chess.

Tournament play[edit]

2013 World Shogi Open Championship (amateur) tournament in Minsk.

There are two organizations for shogi professional players in Japan: the JSA, and the Ladies' Professional Shogi-players' Association of Japan[ja] (日本女子プロ将棋協会?, nihon joshi puro shōgi kyōkai), or LPSA. The JSA is the primary organization for men and women's professional shogi[29] while the LPSA is a group of women professionals who broke away from the JSA in 2007 to establish their own independent organization.[31] Both organize tournaments for their members and have reached an agreement to cooperate with each other to promote shogi through events and other activities.[32] Top professional players are fairly well-paid from tournament earnings. In 2016, the highest tournament earners were Yoshiharu Habu and Akira Watanabe who earned ¥91,500,000 and ¥73,900,000. (The tenth highest earner, Kouichi Fukaura, won ¥18,490,000.)[33]

The JSA recognizes two categories of shogi professionals: Professional (棋士?, kishi), and Female Professional (女流棋士?, joryūkishi). Sometimes kishi are addressed as seikishi (正棋士?), a term from Go used to distinguish kishi from other classes of players. JSA professional ranks and female professional ranks are not equivalent and each has their own promotion criteria and ranking system. In 2006, the JSA officially granted women "professional status". This is not equivalent, however, to the more traditional way of "gaining professional status", i.e., being promoted from the "Shoreikai System" (奨励会?): leagues of strong amateur players aspiring to become a professional. Rather, it is a separate system especially designed for female professionals. Qualified amateurs, regardless of gender, may apply for the "Shoreikai System" and all those who successfully "graduate" are granted kishi status; however, no woman has yet to accomplish this feat (the highest women have reached is Kana Satomi in "Shoreikai 3 dan league", currently one step away from kishi status), so kishi is de facto only used to refer to male shogi professionals.[34]

The JSA is the only body which can organize tournaments for professionals, e.g., the seven major tournaments in the titleholder system and other professional tournaments. In 1996, Yoshiharu Habu became the only kishi to hold all seven existing major titles at the same time. For female professionals, both the JSA and LPSA organize tournaments, either jointly or separately. Tournaments for amateurs may be organized by the JSA and LPSA as well as local clubs, newspapers, private corporations, educational institutions or municipal governments for cities or prefectures under the guidance of the JSA or LPSA.

Since the 1990s, shogi has grown in popularity outside Japan, particularly in the People's Republic of China, and especially in Shanghai. The January 2006 edition of Kindai Shogi (近代将棋?) stated that there were 120,000 shogi players in Shanghai.[35] The spread of the game to countries where Chinese characters are not in common use, however, has been slower.

Computer shogi[edit]

Shogi has the highest game complexity of all popular chess variants. Computers have steadily improved in playing shogi since the 1970s. In 2007, champion Yoshiharu Habu estimated the strength of the 2006 world computer shogi champion Bonanza at the level of two-dan shoreikai.

The JSA prohibits its professionals from playing computers in public without prior permission, with the reason of promoting shogi and monetizing the computer–human events.[36]

On October 12, 2010, after some 35 years of development, a computer finally beat a professional player, when the top ranked female champion Ichiyo Shimizu was beaten by the Akara2010 system in a game lasting just over 6 hours.[37]

On July 24, 2011, computer shogi programs Bonanza and Akara crushed the amateur team of Kosaku and Shinoda in two games. The allotted time for the amateurs was one hour and then three minutes per move. The allotted time for the computer was 25 minutes and then 10 seconds per move.[38]

On April 20, 2013, GPS Shogi defeated 8-dan professional shogi player Hiroyuki Miura[ja] in a 102-move game which lasted over 8 hours.[39]

The highest rated player on Shogi Club 24 is computer program Ponanza, rated 3455 on December 13, 2015.[40]

On April 10, 2016, Ponanza defeated Takayuki Yamasaki, 8-dan in 85 moves. Takayuki used 7 hours 9 minutes.[41]

From a computational complexity point of view, generalized shogi is EXPTIME-complete.[42]

Shogi video games[edit]

Hundreds of video games were released exclusively in Japan for several consoles.

In popular culture[edit]

In the manga series Naruto, shogi plays an essential part in Shikamaru Nara's character development. He often plays it with his teacher, Asuma Sarutobi, apparently always beating him. When Asuma is fatally injured in battle, he reminds Shikamaru that the shogi king must always be protected, and draws a parallel between the king in shogi and his yet-unborn daughter, Mirai, whom he wanted Shikamaru to guide.

Shogi has been a central plot point in manga and anime Shion no Ō, manga and anime series March Comes in Like a Lion [43] and manga and television series 81diver.

In the manga and anime Durarara!!, the information broker Izaya Orihara plays a twisted version of chess, othello and shogi, where he mixes all three games into one as a representation of the battles in Ikebukuro.

See also[edit]

Notes[edit]

  1. ^ a b c "Shogi: Japanese Chess". The Chess Variant Pages. Retrieved 8 March 2012. 
  2. ^ "Sono Hoka no Goshitsumon: Koma no Narabikata ni Kimari wa Aru no Deshōka?" その他のご質問: 駒の並べ方に決まりはあるのでしょうか? [Other questions: Is there a certain way to set up the pieces?] (in Japanese). 日本将棋連盟 (Japan Shogi Association). Retrieved 17 December 2014. 江戸時代は, それぞれの家元に「大橋流」「伊藤流」という並べ方がありました。現在のでも, その並べ方を用いている棋士は少なからずおります. ただし, 決まりとして「このような並べ方をしなければならない」というものはありません. [In the Edo Era, each Iemoto had their own respective way of setting up the pieces: the 'Ohashi-style' and the 'Ito-style'. Although these two styles are still used today by many professionals, there is really no rule specifying that 'the pieces must be set up in this particular way'.] 
  3. ^ Grimbergen, Reijer. "Shogi Terms". www.shogi.net. Retrieved 22 July 2016. 
  4. ^ a b Hosking 1997, p. 19–20.
  5. ^ Hodges, George, ed. (1982). "Who moves first?". Shogi (40): 13. 
  6. ^ a b GNU Shogi manual: The rules of shogi
  7. ^ Hosking (1997: 17)
  8. ^ "Shōgi no Ruru ni Kansuru Goshitsumon — Q: Taikyokuchū ni Ōte wo Kaketara, "Ōte wo Kaketa noni, 'Ōte' to Hasseishinai no wa Hansoku da" to Iwaremashita. Sonoyō na Kitei wa Aru no Deshōka." 将棋のルールに関するご質問 — Q: 対局中に王手をかけたら, 「王手をかけたのに,『王手』と発声しないのは反則だ」と言われました。そのような規定はあるのでしょうか。 [Questions about the Rules of Shogi — Q: I've been told that not saying "Ote" when you place your opponent in check is against the rules. Is there really such a rule?]. 日本将棋連盟 (Japan Shogi Association). Retrieved 9 December 2014. A: たまにそういう主張をされる方がいらっしゃいますが, そのような規定は一切ありません。 [A: Occasionally you will hear such a thing being asserted, but there is absolutely no such rule at all.] 
  9. ^ Hansoku
  10. ^ Fairbairn (1986: 135–136)
  11. ^ Fairbairn (1986: 134, 136–138)
  12. ^ Fairbairn, John (1981). "How to play the fortress opening part 1". Shogi (29): 4–6. 
  13. ^ http://live.shogi.or.jp/ouza/kifu/60/ouza201210030101.html
  14. ^ Fairbairn (1986: 138–139)
  15. ^ Fairbairn (1986: 139)
  16. ^ https://www.shogi.or.jp/faq/rules
  17. ^ http://81dojo.com/documents/Rules_and_Manners_of_Shogi#27-point_Declare_System
  18. ^ 近代将棋 magazine Nov 1983
  19. ^ 将棋世界 magazine Aug 1996
  20. ^ Fairbairn (1986: 158–161)
  21. ^ "Shōreikai Gaiyō" 奨励会概要 [Outline of Shoreikai] (in Japanese). Japan Shogi Association. Retrieved 21 September 2015. 
  22. ^ "Title offset illustration". Retrieved 8 March 2012. 
  23. ^ Hosking 1997, p. 20–21.
  24. ^ Hosking 1997, p. 263–265.
  25. ^ Hitoshi Matsubara, Reijer Grimbergen. "Differences between Shogi and western Chess from a computational point of view". Proceedings: Board Games in Academia. 
  26. ^ Xiaohong Wan, Daisuke Takano, Takeshi Asamizuya; et al. (2012). "Developing intuition: Neural correlates of cognitive-skill learning in caudate nucleus". Journal of Neuroscience (28): 17492–17501. 
  27. ^ Hosking 1997, p. 20.
  28. ^ Fairbairn (1986: 143)
  29. ^ a b "Sōritsu・Enkaku" 創立・沿革 [Founding and History] (in Japanese). 日本将棋連盟 (Japan Shogi Association). Retrieved 16 August 2012. 
  30. ^ Masuda, Kozo (2003). Meijin ni Kyosha wo Hiita Otoko 名人に香車を引いた男 [The Man Who Gave A Lance Handicap To A Meijin]. Chuokoron-Shinsha. p. 223. ISBN 978-4122042476. 
  31. ^ "Enkaku" 沿革 [LPSA History] (PDF) (in Japanese). 日本女子プロ将棋協会 (Ladies' Professional Shogi-players' Association of Japan). Retrieved 26 June 2014. 
  32. ^ "Nihon Joshi Puro Shōgi Kyōkai (LSPA) to Gōisho Teiketsu" 日本女子プロ将棋協会 (LPSA)と合意書締結 [Agreement signed with LPSA] (in Japanese). 日本将棋連盟 (Japan Shogi Association). 2 June 2014. Retrieved 26 June 2014. 
  33. ^ https://www.shogi.or.jp/news/2017/02/201610.html (accessed 2017 Feb 19)
  34. ^ "Yoku Aru Goshitsumon: Naze, Dansei wa "Kishi" na no ni, Josei wa "Joryūkishi" to Naru no Desuka" よくあるご質問:なぜ、男性は「棋士」なのに、女性は「女流棋士」となるのですか。 [FAQ: Why are men referred to as "kishi" and women referred to as "joryūkishi"?] (in Japanese). 日本将棋連盟 (Japan Shogi Association). Retrieved 28 June 2014. 
  35. ^ "shogi population of 120,000 people". 
  36. ^ "Shogi pros warned not to play computers". The Japan Times. Tokyo, Japan. 16 October 2005. Retrieved 28 November 2011. 
  37. ^ "Top female 'shogi' pro falls to computer". Japan Times. Kyodo. 12 October 2010. Retrieved 17 December 2014. 
  38. ^ "Shōgi Sofuto ni Amagumi Kanpai: Hijutsu, Ikki ni Semetsubusareru" 将棋ソフトにアマ組完敗 秘術、一気に攻めつぶされる [Shogi computer programs crush amateurs]. The Asahi Shimbun (in Japanese). 2 August 2011. Retrieved 17 December 2014. 
  39. ^ "Dainikai Shōgi Denōsen Daigokyoku Miura Hiroyuki vs GPS Shōgi" 第2回 将棋電王戦 第5局 三浦弘行八段 vs GPS将棋 [Second Shogi Denosen, Game 5: Hiroyuki Miura 8 dan vs. GPS Shogi] (in Japanese). Niwango. Retrieved 17 December 2014. 
  40. ^ "Computer program Bonkras highest rated player on Shogi Club 24" (in Japanese). Shogi Club 24. 
  41. ^ Shinji, Fukamatsu. "AI beats top shogi player in first match of tournament final:The Asahi Shimbun". The Asahi Shimbun. Retrieved 17 May 2016. 
  42. ^ H. Adachi; H. Kamekawa; S. Iwata (1987). "Shogi on n × n board is complete in exponential time". Trans. IEICE. J70-D: 1843–1852. 
  43. ^ "A Lion's Play of Words". Nihonden. 2017-03-08. Retrieved 2017-03-09. 

References[edit]

  • SHOGI Magazine (70 issues, January 1976 – November 1987) by The Shogi Association (edited by George Hodges)
  • Aono, Teruichi (1983). Better Moves for Better Shogi. translated by John Fairbairn. Tokyo, Japan: Sankaido Publishing Co., Ltd. ISBN 978-4381005977. 
  • Aono, Teruichi (1983). Guide to Shogi Openings: Shogi Problems in Japanese and English. translated by John Fairbairn. Tokyo, Japan: Sankaido Publishing Co., Ltd. ISBN 978-4381005984. 
  • Fairbairn, John (1986). Shogi for beginners (2nd ed.). Ishi Press. ISBN 978-4-8718-720-10. 
  • Habu, Yoshiharu; Hosking, Tony (2000). Habu's Words. translated by Tony Hosking and Yamato Takahashi[ja]. Stratford-upon-Avon, England: The Shogi Foundation. ISBN 978-0953108923. 
  • Hosking, Tony (1997). The Art of Shogi. Stratford-upon-Avon, England: The Shogi Foundation. ISBN 978-0953108909. 
  • Hosking, Tony (2006). Classic Shogi: Games Collection. Stratford-upon-Avon, England: The Shogi Foundation. ISBN 978-0953108930. 
  • Pritchard, D. B. (1994). "Shogi". The Encyclopedia of Chess Variants. Games & Puzzles Publications. pp. 269–79. ISBN 0-9524142-0-1. 
  • Yebisu, Miles (2016). Comprehensive shogi guide in English: How to play Japanese chess. Laboratory Publishing. 

External links[edit]

Rules

Online play

Online tools