Dagger Chess
INVENTED JUNE 1998
FOR THE 1998 CHESS VARIANTS INVENTION CONTEST
Copyright (c) 1998
by david moeser
1. Overview
Dagger Chess is the 39-square version of Hexachess. It's played on a 39-cell board consisting of thirteen ranks of hexagons. The rules of the game are substantially the same as Regular Chess, except that there's no need for castling. Dagger Chess uses the same pieces as Regular Chess, and the movements of the pieces are analogous to the concepts of Regular Chess. A regular chess set can be used with only slight modification.General Information
Hexachess was invented by David Moeser of Cincinnati, Ohio, USA, in the mid-1970s. An information sheet on Hexachess was published around 1983 and has been included as installment #29 in the compilation of articles on chess variants published under the title of NEUE CHESS: THE BOOK.The basic rules of the game and movements of the pieces in Dagger Chess are the same as in Hexachess. The main differences are the shape of the board and the initial position of the pieces. This article will explain the differences and recap the moves of the pieces.
Dagger Chess was invented June 27, 1998, by David Moeser for submission in the 1998 Chess Variants Contest. Interested chessplayers may contact the inventor at the internet e-mail address: erasmus at iglou dot com. The world capital of chess variants is located at: http://www.chessvariants.com/d.chessvar/index.html.
Sheets of paper printed with hexagons for use in board games may be found in many gaming stores.
3. Basic Concepts for Chess Notation
The basic concepts of ranks, files, and diagonals will be explained in the course of illustrating the pieces that move along those lines.3.1 The Rook
On a chessboard consisting of hexagons, ranks and files are the same. They're lines of hexagonal squares (called cells) connected at their edges. The Rook (R) is a rider that moves along file-lines.The term "rank" should be reserved for those "files" running horizontally.
___
___/ x \___
___/ \___/ \___
___/ \___/ x \___/ \___
/ x \___/ \___/ \___/ x \
\___/ x \___/ x \___/ x \___/
/ \___/ x \___/ x \___/ \
\___/ \___/ R \___/ \___/
/ \___/ x \___/ x \___/ \
\___/ x \___/ x \___/ x \___/
/ x \___/ \___/ \___/ x \
\___/ \___/ x \___/ \___/
\___/ \___/ \___/
\___/ x \___/
\___/
3.2 The Bishop
Diagonals are rows of squares (of the same color) that point to each other at their corners. The squares constituting a diagonal do not physically connect to each other. The Bishop (B) is a rider moving along diagonal lines.There are three separate sets (colors) of diagonals on a hex chessboard.
___
___/ \___
___/ x \___/ \___
___/ \___/ \___/ \___
/ \___/ \___/ \___/ \
\___/ \___/ x \___/ x \___/
/ \___/ \___/ \___/ \
\___/ \___/ \___/ \___/
/ x \___/ x \___/ B \___/ x \
\___/ \___/ \___/ \___/
/ \___/ \___/ \___/ \
\___/ \___/ x \___/ x \___/
\___/ \___/ \___/
\___/ \___/
\___/
4. The Dagger Chess Board & Notation
The Dagger Chess board consists of 39 hexagonal squares ("cells") arranged in thirteen ranks. Due to the limitations of ASCII text files, the board in the diagram below is shown tilted at an angle.The shortest rank is each player's back rank, consisting of one square. The longest rank, with five squares, is at the board's middle.
Ranks are lettered 'a' to 'n' ('i' is not used), and squares are numbered left to right. Players playing the Black pieces may find it more convenient to use notation based on their back rank (as in old-style descriptive notation) rather than to denote the board from White's side.
n ___
m ___/ 1 \
l ___/ 1 \___/ n
k ___/ 1 \___/ 2 \
/ 1 \___/ 2 \___/ m
j \___/ 2 \___/ 3 \
h ___/ 1 \___/ 3 \___/ l
___/ 1 \___/ 2 \___/ 4 \
g / 1 \___/ 2 \___/ 3 \___/ k
\___/ 2 \___/ 3 \___/ j
f / 1 \___/ 3 \___/ 4 \
e \___/ 2 \___/ 4 \___/ h
___/ 1 \___/ 3 \___/ 5 \
d / 1 \___/ 2 \___/ 4 \___/ g
\___/ 2 \___/ 3 \___/
c / 1 \___/ 3 \___/ f
\___/ 2 \___/ 4 \ e
b / 1 \___/ 3 \___/d
\___/ 2 \___/
a / 1 \___/ c
\___/ b
a
5. The Pieces and Their Intitial Position
While Regular Chess uses eight pieces and eight Pawns in its initial position, Dagger Chess uses eight pieces and seven Pawns.The initial position of the pieces in Dagger Chess is shown in the diagram below. The King occupies the back rank. The second rank has two Rooks. Three Bishops, one for each color, are on the third rank. Using a regular set, a Pawn may be marked (such as with a rubber band) to denote the third Bishop. Seven Pawns fill out each player's fourth and fifth ranks.
At the start of the game each player has two Knights "in hand." For the purpose of visualizing the initial placement of these Knights, they may be imagined as occupying an imaginary square on the first rank on each side of the King.
black
(also has two knights in hand)
___
___/ k \
___/ r \___/
___/ b \___/ r \
/ p \___/ b \___/
\___/ p \___/ b \
___/ p \___/ p \___/
___/ \___/ p \___/ p \
/ \___/ \___/ p \___/
\___/ \___/ \___/
/ \___/ \___/ \
\___/ \___/ \___/
___/ P \___/ \___/ \
/ P \___/ P \___/ \___/
\___/ P \___/ P \___/
/ B \___/ P \___/
\___/ B \___/ P \
/ R \___/ B \___/
\___/ R \___/
/ K \___/
\___/
WHITE
(also has two Knights in hand)
6. Movements of Other "Regular" Chess Pieces
6.1 The King
The King (K) is a one-square leaper. That is, it moves one square in any direction, either along a file (rank) or along a diagonal. As in Regular Chess, the object of the game is to checkmate the King.
___
___/ \___
___/ \___/ \___
___/ \___/ \___/ \___
/ \___/ x \___/ x \___/ \
\___/ \___/ x \___/ \___/
/ \___/ x \___/ x \___/ \
\___/ x \___/ K \___/ x \___/
/ \___/ x \___/ x \___/ \
\___/ \___/ x \___/ \___/
/ \___/ x \___/ x \___/ \
\___/ \___/ \___/ \___/
\___/ \___/ \___/
\___/ \___/
\___/
6.2 The Queen
The Queen (Q) combines the moves of Rook and Bishop. Thus the Queen is a rider with unlimited scope along both diagonal and file-lines. The initial array for each player does not include a Queen. Queens enter the game only by promotion of Pawns.
___
___/ x \___
___/ \___/ \___
___/ \___/ x \___/ \___
/ x \___/ x \___/ x \___/ x \
\___/ x \___/ x \___/ x \___/
/ \___/ x \___/ x \___/ \
\___/ x \___/ Q \___/ x \___/
/ \___/ x \___/ x \___/ \
\___/ x \___/ x \___/ x \___/
/ x \___/ x \___/ x \___/ x \
\___/ \___/ x \___/ \___/
\___/ \___/ \___/
\___/ x \___/
\___/
6.3 The Knight
The Knight (N) is a leaper with a Y-shaped move. It may be viewed as moving one square along a diagonal and then landing on either of the two squares of the file (rank) immediately beyond. Or, as going one square along a file (rank) and then one square along a diagonal. Either way, the second part is always in an outward direction.
___
___/ \___
___/ x \___/ x \___
___/ x \___/ \___/ x \___
/ \___/ \___/ \___/ \
\___/ \___/ \___/ \___/
/ x \___/ \___/ \___/ x \
\___/ \___/ N \___/ \___/
/ x \___/ \___/ \___/ x \
\___/ \___/ \___/ \___/
/ \___/ \___/ \___/ \
\___/ x \___/ \___/ x \___/
\___/ x \___/ x \___/
\___/ \___/
\___/
6.4 The Pawn
As in Regular Chess, the Pawn (P) does not always capture the same way it moves. The Pawn can move or capture (x) one square forward (toward Black's side) along file-lines. It can also move (o), but not capture, one square forward along the diagonal (directly toward the opponent). [See diagram below.]Clarifying note: Some diagonals lead out at oblique angles from the square a Pawn is on. Pawns do not move on those oblique diagonals. Even tho such movement would make some forward progress, it is not directly toward the opponent's side. The diagonals on which Pawns may move are those that are perpendicular to ranks.
Pawns promote on the opponent's back rank. (I.e., on the King's square in the initial position.)
The diagram below shows the possible movements of a White Pawn on the square 'd2'. (In chess diagrams, White is always shown as moving up the page, and Black is moving downwards.)
___
f/ \___
e \___/ o \___
___/ x \___/ \___
d/ \___/ x \___/ \
\___/ P \___/ \___/f
c/ \___/ \___/e
\___/ \___/ \
b/ \___/ \___/d
\___/ \___/c
a/ \___/b
\___/a
6.5 En Passant
"En passant" pawn capture is the same as in Regular Chess. If a White Pawn (P) on 'd2' [see diagram below] moves to the square 'f2', the Black Pawn (*P*) on 'f3' has seemingly been deprived of the opportunity to capture. Black may capture "en passant" by moving the Pawn to 'e2' and removing the White Pawn from 'f2'.
___
f/ \___
e \___/ o \___
___/ \___/*P*\___
d/ \___/ x \___/ \
\___/ P \___/ \___/f
c/ \___/ \___/e
\___/ \___/ \
b/ \___/ \___/d
\___/ \___/c
a/ \___/b
\___/a
As in Regular Chess, these opposing Pawns are on adjacent lines directly connecting the two players' sides of the board (on this board that means diagonals), and by moving one cell forward along the diagonal the Pawn on 'd2' has leaped two ranks. The Black Pawn on 'f3' would not be allowed to capture "en passant" if the White Pawn moved from 'd2' to 'e1', but it would be allowed to capture normally if the White Pawn on 'd2' moved to 'e2'.
Unlike Regular Chess, on a Hexachess board "en passant' capturing may occur anywhere on the board when the specified situation arises. A Pawn doesn't have to be on its initial square in order to trigger the possibility of "en passant" capture by making a "double jump" move (i.e., one square forward along the diagonal, which leaps to the second-next rank). For example, if the Black Pawn on 'f3' (which is not on its initial square) were to move to 'd3', White's Pawn on 'd2' could capture it "en passant."
Like Regular Chess, the right to capture "en passant" exists only on a player's first turn after the situation arises.
7. Initial Placement of the Knight
At the beginning of the game each player has two Knights "in hand." That is, the Knights start out off the board but may get into the fray by moving or capturing in the manner specified by these rules. Such a Knight move can be made on any turn when such a move is otherwise legal, but when a Knight placement is made it's the only move that player is allowed during that turn.
___
f/ \___
e \___/ \___
___/ \___/ \___
d/ z \___/ \___/ \
\___/ z \___/ \___/f
c/ x \___/ x \___/e
\___/ \___/ x \
b/ \___/ z \___/d
\___/ \___/c
N / \___/b
\___/
N
Solely for the purpose of visualizing this initial placement, the
Knights (N) in the above diagram might be considered to be occupying
the imaginary squares "a-zero" and "a2" of the first ("a") rank. If
such squares actually existed, the Knight on "a0" could move or
capture to squares 'd1', 'd2', or 'c3' (marked with "z"). And the
Knight on "a2" could move or capture to squares 'd3', 'd4', or 'c1'
(marked with "x").
Even tho a Knight has not yet been entered onto the board, it's still a part of the player's initial army and thus it controls the squares (of the third or fourth rank) on which it may enter by moving or capturing. At the start of the game the two Knights "in hand" protect a player's fourth-rank Pawns.
In addition, there's a second way that an offboard Knight may be placed onto the board. If the King's square on the back rack ('a1') is vacant, that player may place a Knight there instead of making some other legal move. Note that an offboard Knight does not control the 'a1' square because it has no power to capture there. (And an offboard Knight does not "control" any squares that it could move to if it were on 'a1' because it isn't yet on the 'a1' square and hence reaching such squares would require two moves!)
A Knight "in hand" may not be captured by the opponent. Also, no piece on the board may move (or "capture") to the imaginary squares of the first rank mentioned above.
[Revision 1.2: July 16, 1998]
Written by David Moeser.
This game is a submission in the contest to design a chess variant on a board with 39 squares.
WWW page created: July 20, 1998.