Tenjiku shogi

Tenjiku shogi (天竺将棋 "tenjiku shōgi," or 天竺大将棋 "tenjiku dai shōgi" "exotic chess") is a large-board variant of shogi (Japanese chess). The game dates back to the 15th or 16th century and was based on the earlier chu shogi, which itself was based on dai shogi.

Rules of the game

Objective

The objective of the game is to capture the opponent's king and, if present, the crown prince, which counts as a second king. Unlike standard shogi, captured pieces may not be dropped back into play by the capturing player.

Game equipment

Two players, Black and White (or 先手 "sente" and 後手 "gote)," play on a board composed of squares in a grid of 16 "ranks" (rows) by 16 "files" (columns) with a total of 256 squares. The squares are undifferentiated by marking or color. A pair of dots may be placed just beyond the fifth rank on each side to mark the promotion zones and aid in the initial setup of the two camps.

Each player has a set of 78 wedge-shaped pieces of 36 types. In all, the players must remember 45 moves for these pieces. The pieces are of slightly different sizes. From largest to smallest (roughly most to least powerful) they are:

* 1 King
* 1 Great general
* 1 Vice general
* 2 Rook generals
* 2 Bishop generals
* 1 Free eagle
* 1 Free king
* 2 Soaring eagles
* 2 Horned falcons
* 2 Water buffalos
* 4 Chariot soldiers
* 2 Fire demons
* 1 Lion hawk
* 1 Lion
* 2 Dragon kings
* 2 Dragon horses
* 2 Rooks
* 2 Bishops
* 1 Kirin
* 1 Phoenix
* 1 Drunken elephant
* 2 Blind tigers
* 2 Ferocious leopards
* 2 Gold generals
* 2 Silver generals
* 2 Copper generals
* 2 Vertical movers
* 2 Side movers
* 2 Reverse chariots
* 2 Vertical soldiers
* 2 Side soldiers
* 2 Lances
* 2 Knights
* 2 Iron generals
* 2 Dogs
* 16 Pawns

Several of the English names were chosen to correspond to rough equivalents in Western chess, rather than as translations of the Japanese names.

Each piece has its name in the form of one or two kanji written on its face. On the reverse side of some pieces are two or three other characters, often in a different color such as red; this reverse side is turned up to indicate that the piece has been promoted during play. The pieces of the two sides do not differ in color, but instead each piece is shaped like a wedge, and faces forward, toward the opposing side. This shows who controls the piece during play.

Table of pieces

Listed below are the pieces of the game and, if they promote, which pieces they promote to. Pieces marked with an *asterisk are only available with promotion.

Game play

Two players alternate making a move, with Black moving first. (The pieces are not differentiated by color; the traditional chess terms "Black" and "White" are only used to indicate who plays first, and to differentiate the sides during discussions of the game.) A "move" consists of moving a piece either to an empty square on the board or to a square occupied by an opposing piece, thus capturing that piece; and optionally of promoting the moving piece, if all or part of its move lies in the "promotion zone". Each of these options is detailed below.

Despite the large size of the board and number of pieces, tenjiku shogi games are often quicker than smaller shogi variants because of the higher average power of the pieces. Good use of the fire demons can make for a short game. Unlike many shogi variants, the very first move can have a very profound effect on the outcome of the game, and indeed it is sometimes wondered whether playing first is an automatic win, barring any mistakes.

Movement and capture

"Tenjiku shogi pieces that occur in chu shogi move as they do in that game."

An opposing piece is captured by "displacement": That is, if a piece moves to a square occupied by an opposing piece, the opposing piece is displaced and removed from the board. A piece cannot move to a square occupied by a friendly piece, that is, by another piece controlled by the moving player. The one exception to this is the unique "burn" of the fire demon.

Each piece on the game moves in a characteristic pattern. Pieces move either "orthogonally" (that is, forward, backward, left, or right, in the direction of one of the arms of a plus sign, +), or "diagonally" (in the direction of one of the arms of a multiplication sign, ×). The vice general, fire demon, lion, and knight are exceptions, in that they do not move, or are not required to move, in a straight line.

Many pieces are capable of several kinds of movement, with the type of movement most often depending on the direction. The movement categories are:

tep movers and limited range movers

Some pieces are limited to moving one square at a time. If a friendly piece occupies an adjacent square, the moving piece may not move in that direction; if an opposing piece is there, it may be displaced and captured.

The step movers are the king, drunk elephant, blind tiger, ferocious leopard, gold general, silver general, copper general, iron general, dog, and pawn. Other pieces may step in certain directions, but move differently in other directions.

Other pieces have a limited range of two squares along a straight line. The water buffalo, chariot soldier, vertical soldier, and side soldier may move one or two squares in certain directions. They can only move to the second square if the first is unoccupied. They may capture on either square, but must stop where they capture.

Area movers

The lion, lion hawk, bishop general, and fire demon may take "multiple" (2 to 3) steps in a single turn. These do not have to be in a line, so these pieces can potentially reach every square within two or three steps of the starting square, not just squares along one of the diagonals or orthogonals. Such moves are also useful to get around obstructions. An area mover must stop where it captures.

Jumping pieces

Some pieces can "jump", or in the case of the knight can only jump: They pass over an intervening piece, whether friend or foe, with no effect on either. These are the free eagle, lion, soaring eagle, horned falcon, tetrarch, kirin, phoenix, and knight. (The lion hawk has this ability in some versions of the game.) These jumps all have a range of two squares: that is, the first square is passed over, and the piece lands (and captures) on the second. The knight jumps "between" the diagonals and orthogonals, and the lion (and lion hawk) may do so.

Ranging pieces

Many pieces can move any number of empty squares along a straight orthogonal or diagonal line, limited only by the edge of the board. If an opposing piece intervenes, it may be captured by moving to that square and removing it from the board. A ranging piece must stop where it captures, and cannot bypass a piece that is in its way. If a friendly piece intervenes, the moving piece is limited to a distance that stops short of the intervening piece; if the friendly piece is adjacent, it cannot move in that direction at all.

The ranging pieces are the great general, vice general, rook general, bishop general, free eagle, soaring eagle, horned falcon, free king, water buffalo, chariot soldier, fire demon, lion hawk, dragon king, dragon horse, rook, bishop, vertical mover, side mover, reverse chariot, vertical soldier, side soldier and lance.

Range jumping pieces

A few powerful pieces may jump over any number of pieces, friend or foe, along a diagonal or orthogonal, but only when making a capture.Fact|date=August 2008 These are the great general, vice general, rook general, and bishop general.

However, they may only jump over other pieces of "lower rank", whether friend or foe. None may jump a king or crown prince of either side. The relevant ranking is:
#King, crown prince
#Great general
#Vice general
#Rook general, bishop general

That is, bishop and rook generals cannot jump any other range-jumping piece.

Some descriptions of the game do not limit this ability to moves making a capture. However, most mention that these pieces have two types of move, ranging and range jumping, suggesting that the capture rule may have been mistakenly omitted.Fact|date=August 2008

Multiple captures

The lion, soaring eagle, horned falcon, and in some rule variants the lion hawk, have sequential multiple-capture abilities, called "lion moves". The fire demon can "burn" multiple pieces simultaneously. These unusual moves are described below.

Other

The heavenly tetrarch cannot move to an adjacent square, and has other idiosyncrasies; the fire demon 'burns' adjacent pieces. This is best described below.

Repeated board positions

A player is not allowed to make a move that would return the board to a previous position, with the same player to move. This rule prevents games from entering into a repeated loop.

Promotion

"Tenjiku shogi pieces that occur in chu shogi promote as they do in that game, with the exception of the free king, which does not promote in chu shogi."

A player's "promotion zone" consists of the five far ranks, at the original line of the opponent's pawns and beyond. As a promotable piece ends a move within the promotion zone—including moves entering, leaving, or moving entirely within the zone,—it has the option of "promoting" to a more powerful rank. (Pieces which take multiple steps per move may promote by crossing into the promotion zone and back out again.) Promotion is effected by turning the piece over after it moves, revealing the name of its promoted rank. Promotion is not mandatory if the unpromoted piece could move further on a later turn, and in some cases it may be beneficial to leave the piece unpromoted. Promotion is permanent and promoted pieces may not revert to their original rank.

Promoting a piece has the effect of changing how that piece moves. See above for what each piece promotes to and below for how they move.

The king, great general, vice general, free eagle, lion hawk, and fire demon do not promote, nor can already promoted pieces promote further.

If a piece which cannot retreat or move to the side advances to the far rank, so that it would otherwise have no further legal move, it is forced to promote. These pieces are the pawn, knight, iron general, and lance. Similarly, a knight reaching the penultimate rank must promote.

If a piece does not promote when it first has the opportunity, it may not promote on its subsequent turn unless it captures or is forced to promote. Thereafter it may promote normally.

Movement diagrams

In the diagrams below, the different types of moves are coded by symbol and by color: Blue for step moves, green for multiple capture, red for range moves, yellow for jumps, and orange for ranging jumps.

*Step: The crown prince can move one square in any direction."Note: The crown prince can move into check at any time."
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bgcolor="#e0e0e0" | White king 王将 "ōshō"
bgcolor="#e0e0e0" | Drunk elephant 酔象 "suizō"
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*Range jump: When making a capture, the vice general can jump any number of lower-ranking pieces along any one diagonal. Otherwise it ranges without jumping.:"It cannot jump a king, crown prince, great general, or another vice general."
*Area move: The vice general can step in any direction, orthogonal or diagonal, up to three times in one turn. That is, it can step in another direction after its first or second step. It need not take all three steps. It must stop when it captures.:"It can return to the square it started from, allowing the player to "skip" a turn."



*Range jump: When making a capture, the rook general can jump any number of lower-ranking pieces along any orthogonal. Otherwise it ranges without jumping.:"It cannot jump a king, crown prince, or another range-jumping general."
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bgcolor="#e0e0e0" | Horned falcon 角鷹 "kakuō"
bgcolor="#e0e0e0" | Soaring eagle 飛鷲 "hijū"
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* Range: It can move any number of free squares along any of the four diagonal directions.
* Step: It can move one square in any orthogonal direction.
The dragon king moves as either a rook or a king.


* Range: The rook can move any number of free squares along any of the four orthogonal directions.
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bgcolor="#e0e0e0" | Ferocious leopard 猛豹 "mōhyō"
bgcolor="#e0e0e0" | Gold general 金将 "kinshō"
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*Step: A pawn can step one square directly forward."Since a pawn cannot move backward or to the sides, it must promote when it reaches the far rank. However, in practice pawns are promoted whenever possible."
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bgcolor="#e0e0e0" | Fire demon 火鬼 "kaki"
bgcolor="#d0d0f0" | Heavenly tetrarch 四天王"shitennō"
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The fire demon may either make a range move or an area move on any one turn. In addition, it has the power to "burn".


*"Igui:" It can capture a piece on any adjacent square without moving. (See "Lion" above.)
*Range: It can move any number of free squares along any one of the four diagonals or along the orthogonal file, skipping any intervening piece on the adjacent square. (It is not a range jumper and cannot jump any other piece.)
*Limited range: It can move two or three squares orthogonally sideways. Although it skips any intervening piece on the first square, it cannot jump a piece on the second square. If it captures on the second square, it must stop there."Note: Western sources do not have the orthogonal range move."

"In English this piece is usually pluralized as 'Heavenly Tetrarchs', though this could refer to all four tetrarchs (the Four Heavenly Kings)."
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bgcolor="#e0e0e0" | Water buffalo 水牛 "suigyū"
bgcolor="#e0e0e0" | Chariot soldier 車兵 "shahei"
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*Range: The side soldier can move any number of free squares orthogonally sideways.
*Limited range: It can move one or two squares directly forward.
*Step: It can move one square directly backward.



*Step: The iron general can move one square forward, either orthogonally or diagonally, giving it three directions of movement."Since an iron general cannot move backward or to the sides, it must promote when it reaches the far rank."
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bgcolor="#e0e0e0" | Free eagle 奔鷲 "honjū"
bgcolor="#e0e0e0" | Lion hawk 獅鷹 "shiō"
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Move according to Edo-era sources:


*Range: The free eagle can move any number of free squares in any of the eight directions, orthogonal or diagonal.
*Jump: It can jump to the second square in any orthogonal direction."Note: If the two cat-sword moves are required to be in different directions, as one of the Edo sources appears to state, and are interpreted as a jump to the second square rather than two actual steps, this is the result."
Move according to TSA rules:


*Double move: The lion can step in any direction, and capture, up to twice in a turn. This move is equivalent to two turns for a king.
**Unlike area movers, the lion can continue after a capture on the first step, capturing up to two pieces on each turn.
**By moving back to its starting square, it can effectively capture a piece on an adjacent square without moving. This is called 居喰い "igui" "stationary feeding".
**A lion next to the promotion zone can make a similar move into and out of the zone, promoting without appearing to move.
*Jump: A lion can jump anywhere within a distance of two squares: That is, anywhere it could reach in two step moves on an empty board, though of course it cannot land on a square occupied by a friendly piece. This is equivalent to jumping in any of the eight diagonal or orthogonal directions, or making any of the jumps of a knight in Western chess, or,
**A jump can be made in place, effectively passing a turn without moving. This is traditionally indicated by tapping the lion and leaving it in place."Note: The restrictions when capturing a lion in chu shogi do not apply in tenjiku shogi."
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bgcolor="#e0e0e0" | Phoenix 鳳凰 "hōō"
bgcolor="#e0e0e0" | Kirin 麒麟 "kirin"
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*Range: The free boar can range any number of free squares along any one of the four diagonal directions, or directly to either side, giving it six directions of movement.



*Range: The vertical mover can move any number of free squares orthogonally forward or backward.
*Step: It can move one square orthogonally sideways.
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bgcolor="#e0e0e0" | Copper general 銅将 "dōshō"
bgcolor="#e0e0e0" | Silver general 銀将 "ginshō"
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*Range: The multi general can move any number of free squares directly forward or diagonally backward, giving it three directions of movement.



*Step: The blind tiger can move one square in any direction except directly forward, giving it seven directions of movement.
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bgcolor="#d0d0f0" | White horse 白駒 "hokku"
bgcolor="#d0d0f0" | Whale 鯨鯢 "keigei"
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*Range: The lance can move any number of free squares directly forward, giving it only one direction of movement."Since a lance cannot move backward or to the sides, it must promote when it reaches the far rank."



*Range: The reverse chariot can move any number of free squares orthogonally forward or backward, giving it two directions of movement.

Check and mate

When a player makes a move, such that the opponent's only remaining king or crown prince could be captured on the following move, the move is said to "give check"; the king or crown prince is said to be "in check". If a player's last king or crown prince is in check and no legal move by that player will get it out of check, the checking move is also "mate", and effectively wins the game.

Unlike Western chess, a player need not move out of check in tenjiku shogi, and indeed may even move into check. Although obviously not often a good idea, a player with more than one royal may occasionally sacrifice one of these pieces as part of a gambit.

A player is not allowed to give perpetual check to the sole objective piece.

Game end

A player who captures the opponent's sole remaining king or crown prince wins the game. In practice this rarely happens, as a player will typically resign when checkmated, as otherwise when loss is inevitable.

A player who makes an illegal move loses immediately. (This rule may be relaxed in casual games.)

Repetition (千日手 "sennichite") is not allowed.

The game reaches an impasse (持将棋 "jishōgi") if all kings and crown princes have advanced into their respective promotion zones and neither player can hope to mate the other or to gain any further material.

Handicaps

Games between players of disparate strength are often played with handicaps. In a handicap game, one or more of White's pieces is removed before the start of play, and White plays the first move of the game.

Alternatively, a strong piece of one player may be removed in exchange for one or more of the other player’s weaker pieces.

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 modifications have been made for tenjiku shogi.

A typical example is P-8g.The first letter represents the piece moved (see above).Promoted pieces have a + added in front of the letter. e.g., +P for a promoted pawn. The designation of the piece is followed by a symbol indicating the type of move: - for an ordinary move or x for a capture. Next is the designation for the square on which the piece lands. This consists of a number representing the file and a lowercase letter representing the rank, with 1a being the top right corner (as seen from Black's point of view) and 16p being the bottom left corner. (This method of designating squares is based on Japanese convention, which, however, uses Japanese numerals instead of letters. For example, the square 2c is denoted by 2三 in Japanese.)

If a lion, horned falcon, soaring eagle or Heavenly Tetrarch captures by "igui", or the fire demon burns, the square of the piece being captured is used instead of the destination square, and this is preceded by the symbol !. A piece moving next to a fire demon (suicide move) is followed by a *. If a double or triple capture is made, than subsequent captures are added after the first capture.

If a move entitles the player to promote the piece, then a + is added to the end to signify that the promotion was taken, or an = to indicate that it was declined.For example, Nx7d= indicates a knight capturing on 7d without promoting.

In cases where the above notation would be ambiguous, the designation of the start square is added after the designation for the piece in order to make clear which piece is meant.

Moves are commonly numbered as in chess.

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

Notes on disputed moves

*Lion hawk:The Shogi Association (TSA) rules interpreted "like a lion" to mean that the lion hawk did not have the full lion powers of jump and double capture, but only a two-step area move. This interpretation was never made on Japanese sites, and has largely been abandoned in the West as well. Giving the lion hawk full lion powers brings the piece more into line with the rest of the game, though both versions are playable. [http://www.iget.me.uk/tenjiku/history.htm]

*Free eagle:Western sources [http://www.iget.me.uk/tenjiku/tutor0.htm] give the free eagle the move of a free king plus the ability to jump to the second square along an orthogonal.

:Japanese Wikipedia states 斜めの場合は飛び越えては行けないが、縦横の場合は駒を飛び越えて行ける "it cannot jump on the diagonals, but can jump pieces on the orthogonals." The diagram shows an orthogonal "range jump," but the free eagle does not appear in the ranking list of range-jumping pieces.

:However, the Edo-era "Sho Shōgi Zushiki" states that it moves 如奔王亦猫刄再度歩兼二行 "as a free king or two times as a cat sword in two directions", which could be taken as requiring the piece to finish on one of the orthogonals, if not exactly a jump; while elsewhere in the "Sho Shōgi Zushiki" and in the "Shōgi Zushiki" it says that 奔王の動きに加えて、猫刄の動き（斜め四方向に1マス動く）を2度できる "in addition to moving as a free king, it can make a cat-sword move (one square in one of the four diagonals) twice", which has no such implication, but which Japanese Wikipedia says is thought to mean a jump.

*Fire demon:TSA rules state that if you move your fire demon next to an opposing fire demon, only your fire demon is immolated; all other adjacent pieces survive. A few computer programs and books stipulate that other adjacent pieces are immolated as well, with only the opposing fire demon surviving, but this interpretation is not widely followed. Both variants are playable. [http://www.iget.me.uk/tenjiku/history.htm]

:Japanese Wikipedia states only that 火鬼が火鬼の隣に移動したときは、動いた方が焼かれる "When a fire demon moves next to a fire demon, the moving piece is burnt," without mentioning the fate of surrounding pieces.

:Edo-era sources differ in whether the orthogonal ranging move is along the rank or the file of the board. Western sources have it move along the file, but moving along the rank would be more in keeping with the fire demon being a promoted water buffalo.

*Heavenly tetrarch:Western sources do not have the ranging move along the orthogonal. However, the "Sho Shōgi Zushiki" states it moves 如車兵亦近八方不行其外周二三要用歩 "as a chariot soldier, also the eight neighboring squares without moving and taking two or three steps outside the periphery", and this is consistent with it being a promoted chariot soldier.

*Range-jumping generals:TSA rules state that the range-jumping generals cannot "capture" an equal or higher-ranking piece, not just that they cannot jump over them. This gives a huge advantage to Black, so that Black can win every game if played right, but is not supported by Japanese sites and has been largely abandoned in the West as unplayable. [http://www.iget.me.uk/tenjiku/history.htm]

See also

* Shogi variant
* Wa shogi
* Chu Shogi
* Heian dai shogi
* Dai shogi
* Dai dai shogi
* Maka dai dai shogi
* Tai Shogi
* Taikyoku shogi

External links

* [http://www.shogi.net/shogi.html Shogi Net]
* [http://www.colina.demon.co.uk/tenjiku.pdf CP Adams' book on tenjiku tactics]
* [http://www.gamerz.net/pbmserv/tenjikushogi.html Gamerz.net/tenjiku shogi]
* [http://history.chess.free.fr/tenjikushogi.htm History.chess/tenjiku shogi]
* [http://www.luckydog.pwp.blueyonder.co.uk/games/tenjiku/ Tenjiku shogi games and problems]