*21 3D chess

It’s NOT 3D chess, Alex, please try to get this right: it’s three-player chess.

Simon

3 Player Class
(as invented by Simon)

1. Pieces laid out in Fig 1. Squares in Fig 2. Green has his pieces at the bottom, his left-hand opponent is Black, his right-hand opponent Orange.

2. Each person has two kings. One, the left king, may only be checked by the left-hand opponent, and the other, the right king, only by the right-hand opponent. The kings are marked with a cross according to the colour of the opponent who is allowed to check it.

3. There are nine kinds of men:

a. 2 kings, cuboids with crosses, marked as above (K)

b. 1 queen, a cuboid with a circle on top (Q)

c. 1 general, a cuboid with a triangle on top (G)

d. 2 rooks, cylinders (R)

e. 3 bishops, cubes (B)

f. 2 ordinary knights, paper clips in cardboard bases (KT)

g. 2 gunner knights, triangular prisms (faces missing) with circles on top (Ng)

h. 2 anti-gunner knights, like gunner knights except for dots on top (Nag)

i. 13 pawns, tetrahedral.

4. Captures are made as in chess, by moving onto a square occupied by the piece. The pawn is an exception that will be dealt with later.

5. The moves of the pieces are as follows:—

a. The bishop moves parallel to the edges of its rhombus, so as to stay on squares of a certain colour e.g. B(GG5) – DE3

b. The rook moves perpendicular to the edges of its rhombus, e.g. R(GH6) – BG3

c. The queen moves like the rook or bishop

d. The king¹ moves like the queen, except only one rhombus at a time

e. The gunner knight moves one rhombus B-wise and one rhombus R-wise, to make a move which cannot be done by the Q e.g. Ng(OG6) – GF6

f. The anti-gunner knight moves like the gunner knight, reversed

g. The ordinary knight moves like one of the two preceding knights

h. The general either moves like an ordinary knight, or moves along its long diagonals, e.g. G(BD6) – BD2.

6. Pawns, when on rhombi pointing to their possessor, move directly forward one rhombus. Take R-wise left or right forward. When on other rhombi, they move directly (R-wise) forward one, two rhombi, or three first time. They take R-wise or B-wise left or right forward. If they move two, three rhombi, they may be taken by a pawn as if it had only moved one rhombus. All pawns may be promoted to any piece (except K), on reaching rhombi from which they cannot move. E.g. (for green ones) P(GF3) – GF4, P(0D2) – BH4, P(BF3) – BE2, P(GE5)xQ(BE3), P(0G4)xR(GE5), P(BD5)xK(GG6), P-GE7 = Q.

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1.it is possible to exchange the two kings if both are in check.

The game is based on that hydrocarbon shape Simon purified in his notebook. It has re-emerged, bubbled back up to the surface from his mathematical depths, confabulated, fluted, overlaid with letters and recaptured numbers, Sellotaped to a sheet of lined file paper, and ready for use in your tutor’s pipe-smoke-filled room.

The top half of the illustration on page 182 is the playboard. As ordinary chess has black squares and white squares, a three-dimensional chessboard (for three players) has black diamonds, white diamonds, and diamonds labelled ‘A’.

The bottom half gives the location reference for each diamond.

Here’s a tidier version of the playboard, with the diamonds labelled ‘A’ replaced by grey-shaded diamonds:

Each of the three players has:

Two Kings (K) , one Queen (Q) , one General (G) , two Rooks (R) , three Bishops (B) , two ordinary Knights (Kt) (represented by ‘paper clips in cardboard bases’), two Gunner Knights (Ng) , two Anti-gunner Knights (Nag) and thirteen Pawns (P).