Chess on a really big board

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Chess on a really big board: initial position. As Betza did not specify icons for the unorthodox pieces, instead using letters to represent them in diagrams (as for the standard pieces), some Omega Chess symbols have been used to represent some of the unorthodox piece types, along with some relatively standard icons for the knighted pieces from Capablanca chess, and an inverted knight for the rose.

Chess on a really big board is a large chess variant invented by Ralph Betza around 1996.^[1] It is played on a 16×16 chessboard with 16 pieces (on the back rank) and 16 pawns (on the second rank) per player. Since such a board can be constructed by pushing together four standard 8×8 boards, Betza also gave this variant the alternative names of four-board chess^[1] or chess on four boards.^[2]

Game description

The standard rules of chess apply except in the following cases:^[1]

• The game is played on a 16×16 board with the starting position shown above.
• An unmoved pawn can move one step, up to the middle of the board (in the case of the 16×16 board, the eighth rank), or anything in between. Thus, 1.i8 is a legal opening move, and so are 1.i3, 1.i4, 1.i5, 1.i6, and 1.i7. Once it has moved for the first time, it can only make one step at a time. (In the case of an 8×8 board, this is exactly the same as in standard chess). Such a long initial pawn move allows the moving pawn to be captured en passant by an enemy pawn as if it had stopped on any one of the squares it had passed through.
• In castling, the rook moves the same distance as it does in chess. Thus, the king moves further; if it castles kingside, it ends on the second-rightmost file, and if it castles queenside, it ends on the third-leftmost file. On the 16×16 board, 0-0 leaves the rook on the n-file and the king on the o-file, and 0-0-0 leaves the rook on the d-file and the king on the c-file.
• The 50-move rule becomes at least a 100-move rule. Generally, if each of the board's dimensions is multiplied by n, the number of non-capturing or non-pawn moves allowable before draw claims become possible must also be multiplied by at least n.
• There are extra fairy chess pieces that move differently, although the orthodox pieces are retained. Their movements are given below using Ralph Betza's "funny notation". In physical play, these six types of fairy pieces may be represented by pieces from mismatched chess sets. Note that Betza did not specify icons or designs for the fairy pieces for diagrams, instead using letters to represent them: the diagrams here use common renderings for the archbishop and chancellor, an inverted knight for the rose, and Omega Chess pieces for the remaining three fairy piece types.^[3]

a b c d e f g h 8 8 7 7 6 6 5 5 4 4 3 3 2 2 1 1 a b c d e f g h FD (single-letter symbol D). Moves as ferz or dabbaba. (This is the kirin from chu shogi and dai shogi.) Can jump for all moves. In his The Encyclopedia of Chess Variants, David Pritchard calls this piece a unicorn.[2]

a b c d e f g h 8 8 7 7 6 6 5 5 4 4 3 3 2 2 1 1 a b c d e f g h WFA (single-letter symbol W). Moves as king or alfil. Can jump for all moves. In his The Encyclopedia of Chess Variants, David Pritchard calls this piece an elephant.[2]

a b c d e f g h 8 8 7 7 6 6 5 5 4 4 3 3 2 2 1 1 a b c d e f g h Superknight (NLJ; single-letter symbol J). Moves as knight, camel, or zebra. Can jump for all moves. Known as the buffalo in the fairy chess tradition.

a b c d e f g h 8 8 7 7 6 6 5 5 4 4 3 3 2 2 1 1 a b c d e f g h Archbishop (NB; single-letter symbol A). Moves as bishop or knight. Can jump for knight moves. Known as the princess in the fairy chess tradition.

a b c d e f g h 8 8 7 7 6 6 5 5 4 4 3 3 2 2 1 1 a b c d e f g h Chancellor (RN; single-letter symbol C). Moves as rook or knight. Can jump for knight moves. Known as the empress in the fairy chess tradition.

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Rose (qN; single-letter symbol O). Makes any number of consecutive knight moves on an octagonal (almost circular) path. It may move either clockwise or counterclockwise: going along a sequence of numbers 1-2-3-4-3-2-1 in a circle on the diagram demonstrates one possible move of the rose. For example, it may travel along the following path: i8–g9–e8–d6–e4–g3–i4–j6–i8. It may jump over pieces in each of its individual knight moves, but is blocked by pieces on its circular path (though it may capture an enemy piece thus placed).

By going all the way around a circle, it is allowed to return to its starting position. Thus a player with an unblocked rose may pass their turn.

The rose was invented in 1968 by Robert Meignant for chess problems.^[2]

Betza included the rose in his initial setup because it is a piece especially suited for a large board: it cannot display its full power on boards smaller than 13×13. Furthermore, its already large move still cannot reach all the way across the board, contributing to the large feeling of the game along with the ability of the riders to attack from a large distance away.^[1]

History

Chess on a really big board was created as an outgrowth of Betza's ideas on three-dimensional chess, after he noted that an 8×8×8 board for 3D chess would have 512 spaces, more than any large version of chess that had previously been invented; he then considered two-dimensional very large (or, in his word, "huge") chess games, mainly on the 16×16 board because such a board requires no non-standard equipment to construct, and while much larger than the 8×8 board, it was not so big as to make an unplayable game.^[1] This idea eventually came full circle in the development of the 16×16×16 three-dimensional version of chess on a really big board, which he called "impossibly large".^[4]

Gameplay

Betza described his choice of pieces as "a very basic and logical selection of the fundamental geometrical moves, except for my idiosyncratic insistence on including the Rose in the lineup of pieces. These are largely the basic units of chess, and anybody who designs a [16×16] game with 32 pieces is bound to come up with something reasonably similar, at least if they want it to be like chess but a bit less tactical." In fact, his original plan was to include the WA along with the complementary FD, but this leaves the c- and n-pawns undefended in the initial position. His final assessment was that the game was "rather chesslike".^[1]

Betza divided the pieces into three classes: seven long-range pieces (the rooks, bishops, queen, archbishop, and chancellor), two mid-range pieces (the rose and superknight), and six short-range pieces (the knights, FDs, and WFAs). He opined that the short-range pieces, though the weakest, were crucial as they take time to get into the action, but are very important for opening up specific lines for attacks.^[1]

Sample opening phase of a game

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Position after 9...Ql12

The following sample game fragment was constructed by Betza.^[1]

1.i8 i9

2.Qp9

The 16×16 analogue to the Wayward Queen Attack (in orthodox chess, 1.e4 e5 2.Qh5). On such a large board, this opening move becomes much sounder, as it is more difficult to attack the queen, and from this position it bears down onto the centre from a long distance.

2...h10

3.j8 Oh11

Black defends his i-pawn; White attacks it again (her j-pawn being defended by the chancellor on j1); Black defends it again, moving his rose from f16 via e14 and f12 to h11, where it defends the pawn on i9. Trading pawns would be disadvantageous and lead to the loss of a tempo by the initiator, but at some point White's chancellor must be developed.

Currently, White has no immediate threats. Attacks on Black's h-pawn with Bb4 (moving the d-pawn away first), or his rose with Bo4 (moving the m-pawn away first) are easy to counter. Hence she decides to bring a short-range piece to attack, though this will take several turns.

4.Ji4 Ai15

5.Jh6 Ak14

Attacking White's queen.

6.Qp10 Ji13

7.p8!?

Threatening to lift the king's rook to the h-file to contest the centre.

7...An11!?

Continuing to attack White's queen. This region could also be used as an advanced base: the n11 square can easily be defended by the rose or the m-pawn, and a natural follow-up would be 8...Qn10.

8.Ql6 Ak8

The White queen retreats and attacks the Black i-pawn again, but Black defends the pawn with the archbishop while attacking the queen again. The archbishop itself, though attacked by White's superknight, is protected by Black's rose.

9.Qo3

If 9.Qk7, then 9...Al9 may win a pawn.

9...Ql12

Threatening 10...Al6.^[1]

Sample games

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Final position of game 1 after 53.Kj2