Shogi

Shogi (将棋), (rhymes with yogi) in English, also known as Japanese chess, is a two-player  board game in the same family as  Western chess, chaturanga, Chinese Xiangqi, and is the most popular of a family of chess variants native to Japan. Shōgi means general's (shō 将) boardgame (gi 棋). In early years, however, shogi was written 象棋 (the same as Xiangqi, "elephant chess").

The earliest predecessors of the game, chaturanga, originated in India in the 6th century AD,  and spread from China to Japan, where it spawned a number of variants. 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was played as early as the 16th century, while a direct ancestor without the "drop rule" was recorded from 1210 in a historical document Nichūreki, which is an edited copy of Shōchūreki and Kaichūreki from the late Heian period (ca 1120).

According to ChessVariants.com, "Perhaps the enduring popularity of Shogi can be attributed to its 'drop rule'; it was the first chess variant wherein captured pieces could be returned to the board to be used as one's own. David Pritchard credits the drop rule to the practice of 16th century mercenaries who switched loyalties when captured—no doubt as an alternative to execution."

Game equipment


Two players, Sente 先手 (Black) and Gote 後手 (White), 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 almost always made of rectangles; square boards are very uncommon.

Each player has a set of 20 wedge-shaped pieces of slightly different sizes. Except for the kings, opposing pieces are differentiated only by orientation, not by marking or color. From largest to smallest (most to least powerful), the pieces are:


 * 1 king
 * 1 rook
 * 1 bishop
 * 2 gold generals
 * 2 silver generals
 * 2 knights
 * 2 lances
 * 9 pawns

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 colour (usually red); this side is turned face up during play to indicate that the piece has been promoted. The pieces of the two players do not differ in colour, but instead each faces forward, toward the opposing side. This shows who controls the piece during play.

The Japanese characters have deterred many people from learning shogi. This has led to "Westernized" or "international" pieces, which replace the characters with iconic symbols. However, partially because the traditional pieces are already iconic by size, with more powerful pieces being larger, most Western players soon learn to recognize them, and Westernized pieces have never become popular.

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

* The kanji 竜 is a simplified form of 龍.

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 promoted rank 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 金 'gold', becoming more cursive (more abbreviated) as the value of the original piece decreases. These cursive forms have these equivalents in print: 全 for promoted silver, 今 for promoted knight, 仝 for promoted lance, and 个 for promoted pawn (tokin). Another typographic convention has abbreviated versions of the unpromoted ranks, with a reduced number of strokes: 圭 for a promoted knight (桂), 杏 for a promoted lance (香), and the 全 as above for a promoted silver, but と for tokin.

Setup and gameplay
Each player sets up his pieces facing his opponent.
 * In the rank nearest the player he places:
 * The king is placed in the center file.
 * The two gold generals are placed in the adjacent files 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 $\overline{ |L|N|S|G|K|G|S|N|L| }$.
 * 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 to each file.

Traditionally, even the order of placing the pieces on the board is determined. There are two recognized orders, ohashi and ito. Placement sets pieces with multiples (generals, knights, lances, pawns) from left to right in all cases, and follows the order:


 * King
 * Gold generals
 * Silver generals
 * Knights
 * In Ito, the player now places pawns
 * Lances
 * Bishop
 * Rook
 * In Ohashi, the player now places pawns

The players alternate taking turns, with Black (the side containing the Jeweled General) playing first. The terms "Black" and "White" are used to differentiate the two sides, but there is no actual difference in the color of the pieces. For each turn a player may either move a piece which is already on the board (and potentially promote it, capture an opposing piece, or both) or else "drop" a piece that has already been captured onto an empty square of the board. These options are detailed 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.

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

Every piece blocks the movement of all other non-jumping pieces through the square it occupies. However, 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. It is not possible for the capturing piece to continue beyond that square on that turn.

It is common to keep captured pieces on a wooden stand (or 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. This is because captured pieces, which are said to be in hand, have a crucial impact on the course of the game.

The knight jumps, that is, it passes over any intervening piece, whether friend or foe, without an effect on either. It is the only piece to do this.

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.

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

King
A King can move one square in any direction, orthogonal or diagonal.

Rook
A rook can move any number of free squares along any one of the four orthogonal directions.

Bishop
A bishop can move any number of free squares along any one of the four diagonal directions.

Because they cannot move orthogonally, the opposing unpromoted bishops can only reach half the squares of the board, unless they are captured and then dropped by the opposing player.

Gold general
A gold general can move one square orthogonally, or one square diagonally forward, giving it six possible destinations. It cannot move diagonally backward.

Silver general
A silver general can move one square diagonally or one square directly forward, giving it five possibilities.

Because an unpromoted silver can retreat more easily than a promoted one (see below), it is very common to leave a silver unpromoted at the far side of the board.

Knight
A knight jumps at an angle intermediate between orthogonal and diagonal, amounting to one square forward plus one square diagonally forward, in a single motion. That is, it has a choice of two forward destinations. It cannot move to the sides or backwards.

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 (see below) at the far side of the board. However, since a knight cannot move backward or to the sides, it must promote when it lands on one of the two far ranks and would otherwise be unable to move further.

Lance
A lance can move any number of free squares directly forward. It cannot move backward or to the sides.

It is often useful to leave a lance unpromoted (see below) at the far side of the board. However, since a lance cannot move backward or to the sides, it must promote if it arrives at the far rank.

Pawn
A pawn can move one square directly forward. It cannot retreat.

Since a pawn cannot move backward or to the sides, it must promote (see below) if it arrives at the far rank. However, in practice, a pawn is promoted whenever possible.

Unlike the pawns of international chess, shogi pawns capture the same way they otherwise move, directly forward.

There are two restrictive rules for where a pawn may be dropped. (See below.)

Promotion
A player's promotion zone is the far third of the board, the three ranks occupied by the opposing pieces at setup. If a piece moves across the board and part of that path lies within the promotion zone, that is, if it moves into, out of, or wholly within the zone, but not if it is dropped (see below), then that player may choose to promote the piece at the end of the turn. Promotion is indicated by turning the piece over after it moves, revealing the character for the promoted rank.

If a pawn or lance reaches the far rank or a knight reaches either of the two farthest ranks, it must promote, as it would otherwise have no legal move on subsequent turns. A silver general never needs 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.

When captured, pieces lose their promoted status. Otherwise promotion is permanent.

Promoting a piece has the effect of changing how that piece moves. Each piece promotes as follows:


 * A silver general, knight, lance, or pawn replaces its normal power of movement with the power of a gold general.
 * A rook or bishop keeps its original power of movement and gains the power to move one square in any direction, like a king. This means that a promoted bishop is able to reach any square on the board, given enough moves.
 * A king or a gold general cannot promote, nor can pieces which are already promoted.

Promoted rook
A promoted rook (dragon king) may move as a rook or as a king, but not as both on the same turn.

Promoted bishop
A promoted bishop ("dragon horse") may move as a bishop or as a king, but not as both on the same turn.

Drops
Captured pieces are truly captured in shogi. They are retained "in hand", and can be brought back into play under the capturing player's control. On any turn, instead of moving a piece on the board, a player may take a piece that had been previously captured and place it, unpromoted side up, on any empty square, facing the opposing side. The piece is now part of the forces controlled by that player. This is termed dropping the piece, or just a drop.

A drop cannot capture a piece, nor does dropping within the promotion zone result in immediate promotion. However, either capture or promotion may occur normally on subsequent moves by the piece.

A pawn, knight, or lance may not be dropped on the far rank, since it would have no legal move on subsequent turns. Similarly, a knight may not be dropped on the penultimate rank.

There are two other restrictions when dropping pawns:


 * 1) A pawn cannot be dropped onto the same file (column) as another unpromoted pawn controlled by the same player (Promoted pawns do not count). A player who has 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) A pawn cannot be dropped to give an immediate checkmate. However, other pieces may be dropped to give immediate checkmate, a pawn that is already on the board may be advanced to give checkmate, and a pawn may be dropped so that either it or another piece can give checkmate on a subsequent turn.

It is common for players to swap bishops, which oppose each other across the board. This leaves each player with a bishop "in hand" to be dropped later, and gives an advantage to the player with the stronger defensive position.

Checkmate and winning the game
When a player makes a move such that the opposing king could be captured on the following 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 and no legal move by that player will get the king out of check (which is necessary whenever possible ), the checking move is also checkmate (tsumi 詰み) and effectively wins the game. In practice this rarely happens, as a player will concede defeat when loss is inevitable.

To give the warning "check!" in Japanese, one says "ōte!" (王手). However, this is an influence of international chess and is not required, even as a courtesy.

A player is not allowed to give perpetual check.

In professional and serious amateur games, a player who makes an illegal move loses immediately.

There are two other possible, if uncommon, ways for a game to end: repetition (千日手 sennichite) and impasse (持将棋 jishōgi).

If the same game position occurs four times with the same player to play, the game is considered a draw. For two positions to be considered the same, the pieces in hand must be the same as well as the positions on the board. However, if this occurs with one player giving perpetual check, then that player loses.

The game reaches an impasse 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. If this happens, the winner is decided as follows: Each rook or bishop scores 5 points for the owning player, and all other pieces except kings score 1 point each. (Promotions are ignored for the purposes of scoring.) 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 this impasse generally needs to be agreed on for the rule to be invoked, a player may refuse to do so, on the grounds that he/she could gain further material or position before an outcome has to be decided. If that happens, one player may force jishōgi upon getting his king and all his pieces protected in the promotion zone.

In professional tournaments the rules typically require drawn games to be replayed with colours (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 Nakahara Makoto and Kato Hifumi was unusual in this regard, with jishōgi in the first game (only the fifth draw in the then 40-year history of the tournament), a game which lasted for an unusual 223 moves (not counting in pairs of moves), with an astounding 114 minutes spent pondering a single move, and sennichite in the sixth and eighth games. Thus this best-of-seven match lasted ten games and took over three months to finish; Black did not lose a single game and the eventual victor was Katō at 4-3.

Player ranking and handicaps
Amateur players are ranked from 15 kyū to 1 kyū and then from 1 dan and upwards; this is the same terminology as many other arts in Japan. Professional players operate with their own scale, from professional 4 dan and upwards to 9 dan for elite players. Amateur and professional ranks are offset (with amateur 4 dan being equivalent to professional 6 kyu).

Games between players of disparate strengths are often played with handicaps. In a handicap game, one or more of White's pieces are removed from the setup, and in exchange White plays first. Note that the missing pieces are not available for drops and play no further part in the game. The imbalance created by this method of handicapping is not as strong as it is in international chess because material advantage is not as powerful in shogi.

Common handicaps, in increasing order of severity, include:
 * Left lance
 * Bishop
 * Rook
 * Rook and left lance
 * Two pieces: Rook and bishop
 * Four pieces: Rook, bishop, and both lances
 * Six pieces: Rook, bishop, both lances and both knights

Other handicaps are also occasionally used. The relationship between handicaps and differences in rank is not universally agreed upon, with several systems in use.

If a jishōgi occurs in a handicap game, the removed pieces are counted as if White had them in play, or available for drops.

Game notation
The method used in English-language texts to express shogi moves was established by George Hodges in 1976. It is derived from the algebraic notation used for chess, but differs in several respects. It is not used in Japanese-language texts, as it is no more concise than kanji.

A typical move might be notated P-8f. The first letter represents the piece moved: P for Pawn. (There is also L lance, N knight, S silver, G gold, B bishop, R rook, K king, as above.) Promoted pieces are indicated by a + in front of the letter: +P is a tokin (promoted pawn).

Following the abbreviation for the piece is a symbol for the type of move: – for a simple move, x for a capture, or * for a drop. Next is the square on which the piece lands. This is indicated by a numeral for the file and a lowercase letter for the rank, with 1a being the top right corner (as seen by Black) and 9i being the bottom left corner. This is based on Japanese convention, which, however, uses Japanese numerals instead of letters. For example, square 2c is "2三" in Japanese.

If a move entitles the player to promote, then a + is added to the end if the promotion was taken, or an = if it was declined. For example, Nx7c= indicates a knight capturing on 7c without promoting.

In cases where the piece is ambiguous, the starting square is added to the letter for the piece. For example, at setup Black has two golds which can move to square 5h (in front of the king). These are distinguished as G6i-5h (from the left) and G4i-5h (from the right).

Moves are numbered per player's move, unlike chess which counts each pair of moves as one move. For example, the start of a game might look like this: 1. P-7f  2. P-3d 3. P-2f  4. G-3b 5. P-2e  6. Bx8h+ 7. Sx8h  8. S-2b

In handicap games White plays first, so Black's move 1 is replaced by an ellipsis.

Strategy and tactics
Shogi is similar to chess but has a much larger game tree complexity because of the use of drops. However, like chess, 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 and positioning for attack, the mid game consists of attempting to break through the opposing defenses while maintaining ones own, and the end game starts when one side's defenses have been compromised.

History
"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 Changgi 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) (ca. 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. However, there is no clear record of when drops were introduced.

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. However, it is thought that these were only played to a very limited extent. 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 (東京将棋同盟社) was formed. This was an early incarnation of the modern Japan Shogi Association (日本将棋連盟), founded in 1997.

In 1935, meijin Sekine Kinjirō stepped down, and the rank of meijin came to be awarded to the winner of a Meijin title match (名人戦). 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) 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.

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), which isn't recognised 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
In 1996, Yoshiharu Habu won all seven titles; in 2008 he held four. In 2006, the Shogi Association admitted women to the ranks of professionals (正棋士).

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

Computer shogi
Shogi has the highest game complexity of all popular chess variants. Therefore, Shogi is the hardest of the popular chess variants in terms of programming the computer to beat the highest rated player. Computers have steadily improved in playing shogi since the 1980s. In 2007, champion Yoshiharu Habu estimated the strength of the 2006 world computer shogi champion Bonanza at the level of 2-dan shoreikai. Tools used by shogi programmers are the GUI Shogidokoro, shogi server Floodgate and the annual computer tournaments. The Japan Shogi Association prohibits professionals from playing computers.