Brusky's Hexagonal Chess

Setup

Brusky's Hexagonal Chess is played on a hexagonal board with horizontal ranks and slanting files. There are two sets of files, but only one is needed for notation. The convention used in this game is to give the same file label to the spaces in left leaning files. So, for example, the left leaning file from White's left corner is a1-a2-a3-a4-a5, whereas the right-leaning file from the same space is a1-b2-c3-d4-e5-f6-g7-h8. This difference has no effect on how pieces move and is only a convention for establishing a system of notation. This board has 12 files and 8 ranks. Files d through i cover all 8 ranks, but a covers only ranks 1 to 5, b covers only ranks 1 to 6, c covers only ranks 1 to 7, j covers only ranks 2 to 8, k covers only ranks 3 to 8, and l covers only ranks 4 to 8. This gives the board a more symmetrical shape than the parallogram it was cut out of, leaving it with only 2*5 + 2*6 + 2*7 + 6*8 = 84 spaces.

At each end of the board, each player has a rank with 9 spaces. From each player's left to the same player's right, each player has a Rook, a Knight, a Bishop, a Queen, a Bishop, a King, a Bishop, a Knight, and a Rook. The next rank has 10 spaces and is filled with Pawns. This setup gives the game rotational symmetry, meaning each side looks the same when the board is rotated 180 degrees.

Pieces

Except for details concerning castling and Pawn movement, the pieces in this game move exactly like the pieces in Glinksi's Hexagonal Chess.

King

The King moves ones space in any orthogonal or diagonal direction. Orthogonal directions go through the sides of spaces, and diagonal directions go through the corners of spaces. With six sides and six corners, the King can move in up to 12 different directions.

For King-side castling, the King moves two spaces toward the Rook, and for Queen-side castling, the King moves three spaces toward the Rook. Apart from moving further for Queen-side castling, castling works the same as it does in Chess. The Rook moves to the space adjacent to the King on its other side, and all usual castling conditions apply.

Rook

The Rook may move any number of spaces in any orthogonal direction until it reaches an occupied space.

Bishop

The Bishop may move any number of spaces in any diagonal direction until it reaches an occupied space. As in Chess, Bishops are colorbound. Unlike Chess, the board has three colors, and each player has three Bishops to have one for each color. Because each Bishop can reach only one third of the board, a Bishop is less powerful than it is on the Chess board, where it can reach half the spaces.

Queen

The Queen moves as a Rook or a Bishop. Note that it can reach any space in its third perimeter, which it cannot do on a square board.

Knight

The Knight can leap directly to any space in its fourth perimeter that a Queen cannot reach. As in Chess, each space it can leap to is one that could be reached by moving one space orthogonally, followed by one more space in an outward diagonal direction. Besides not including the inward diagonal directions, outward diagonal directions do not include the sideways diagonal directions that would turn the piece a full 90 degrees.

Pawn

• A Pawn normally moves ones space orthogonally forward without capturing or one space diagonally forward to capture, as shown for the c4 Pawn in the diagram below.
• On its first move, as shown for the k7 Pawn, a Pawn may move two spaces orthogonally forward. Since each Pawn has two different orthogonally forward directions it can go in, it should also be noted that its double step move cannot change direction. Each step must be in the same orthogonal direction. This is why the k7 Pawn cannot move to the empty j5.
• Capturing moves are normally limited to slanted diagonal directions, which is why the King on d6 is not in check from the c4 Pawn. But from its starting space, a Pawn may also capture diagonally in the fully vertical diagonal direction, which is why the f2 Pawn can capture the Knight on g4.
• If a Pawn is blocked by an enemy piece in one orthogonally forward direction, it is also blocked in the other. Since the Pawns on f2 and g3 are blocking each other, neither one can move orthgonally forward in the open direction. This kind of blocking works only with adjacent pieces. So, even though the Queen blocks the i2 Pawn from moving to i4, this does not block it from moving to k4. While the rules I have read have been unclear on this point, I got confirmation of this interpretation by playing out a the game between O. Yefimov and Ya. Brusky in Pritchard's Encyclopedia of Chess Variants. At one point, a White Pawn on j2 moved to l4 even though Black had a Pawn on j4. After White's move, Black captured White's Pawn by en passant, moving from j4 to k3.
• After a Pawn makes a double move, it may be captured by en passant by any Pawn that could have captured it if it had moved to the space it passed over. The Pawn captures it by moving to the space it would have been able to capture it on if it had only one space. This is the same as Chess and is not depicted.

Rules

This game follows the rules of Chess in every respect except those already described above.

Notes

This description of the game is based on the section about the game in the "HEXAGONAL C" article of the first edition of D. B. Pritchard's book The Encyclopedia of Chess Variants, and it follows it in every detail. As mentioned above, I had to play out one of the included games to confirm one interpretation of the rules. The chapter on Boards based on Hexagons in The Classified Encyclopedia of Chess Variants leaves out some details and applies the same system of notation to every hexagonal variant despite it not being historically accurate. In researching the rules, I checked out different programmed versions of the game, and I found that none of these got the rules 100% correct.

• Greenchess doesn't allow an unmoved Pawn to capture in the fully vertical diagonal direction, and it allows Pawns that are blocked in one direction by an enemy piece to still move in the other direction.
• Ed Friedlander's Java applet does not handle double moves for Pawns or castling for Kings, and it lets moved Pawns capture diagonally in the fully vertical direction.
• Jocly moves the King only two spaces for Queen-side castling, and it allows Pawns that are blocked in one direction by an enemy piece to still move in the other direction.
• Ludii does not let a Pawn move forward in the open direction when it is blocked by a friendly piece, but the rule is that only an enemy piece can block a Pawn's move in the open direction.

Board Images

Here are blank board images you can print out and use to play the game with small Chess pieces. I will link to the Diagram Designer to make it easy for you to modify them before printing. You should print the board in landscape at the maximum size that will fit the page. This was 145% for letter size when I did it.

• Monochrome board for black ink
• Earthtone board for color ink

Last revised by Fergus Duniho.