25.4 Square Boards on five levels

Raumschach [Maack], also known as Space Chess (Ferdinand Maack, 1907 and subsequently). The classic 3-D game. Its inventor contended that to make chess properly analogous to modern warfare, attack must be possible from above and below (air/underwater) as well as on the surface. Maack promoted space chess with demonstrations, articles, booklets and a magazine (Raumschach). The game was originally set on an 8×8×8 board as described later, but Maack experimented with other boards and 5×5×5 became the normal form. In 1919 he founded the Hamburg Space-Chess Club, which survived until World War II. Dawson in particular was attracted to Maack’s 5×5×5 invention — ‘the game which will naturally be the commonplace of the future’ — and he ran a series of articles on it (Chess Amateur, July-December 1926). Each player has two extra pieces (unicorns as described above), and there are 10 pawns a side; White RNKNR fronted by 5×P on board A, BUQBU fronted by 5×P on board B, Black diametrically opposite on boards E and D (unicorns on Da5 and Dd5). White pawns promote on rank E5, black on rank A1. N makes one step as R and one as B (if you prefer a mathematical definition, it is a ‘2-1-0 leaper’). P moves one step at a time and captures diagonally forward, all movement being towards the promotion rank. Thus WP at Ab2 can move to either Ab3 or Bb2, and it can capture on any of the five squares Aa3, Ac3, Ba2, Bc2, Cb3¹. Another array halves the number of pawns and has all white men on level A, all black men on level E: (Aa1–e1 / Ee5–a5 and inwards) RNKNR, BUQBU, 5×P.

The game has attracted many leading problemists. Troitsky studied the endings and showed that K+Q always wins against K.

1. Pritchard erred; it should read Bb3, not Cb3.