This source contains, among other things, a complete game between experienced players.
Fairy Chess Review, December, 1945.
Deutsche Schachzeitung 1878
The board is a cube divided into 5 pieces in each of the three coordinate planes, creating a 125-cube playing volume. The cubes are alternately coloured black and white for convenience, although four-colour schemes have been advocated to allow for easy visualisation of the moves of the Unicorn (see below), just as the two-colour scheme permits easy visualisation of the moves of the Bishop.
The dimensions of the human hand, etc. suggest that the squares should be about 2 inches (5 cm) wide and the board separation should be between 5 and 7 inches, depending on the size of the pieces and the care with which one is willing to move the pieces. The "black" squares should actually be colored with a translucent paint to facilitate the visualisation of bishop moves.
Symbol Piece K King Q Queen R Rook B Bishop S Knight (German: Springer) U Unicorn (German: Einhorn) P Pawn
Remember that each of the planes that holds one coordinate constant can be thought of as 2D chess board in its own right. In other words, for example, the set of squares at the front of the board, namely
xy1, where x and y are arbitrary, forms a two dimensional board, within which the 2D rules apply. The rules for other cases are similar.
Detailed description of each piece's moves:
Ccx (i.e. along a file) Cx3 (i.e. along a rank) Xc3 vertically, along a column
A bishop positioned at Cc3 on an empty board can move to Cd4, Ce5, Cb2, Ca1, Cd2, Ce1, Cb4, Ca5, exactly as in 2D chess Dd3, Ee3, Bb3. Aa3, Db3, Ea3, Bd3, Ae3, in the front plane, Bc2, Ac1, Dc4, Ec5, Bc4, Ac5, Dc2, Ec1 in the side plane, and nowhere else.
NOTE: The bishop's move is perhaps key to understanding this game. A bishop, in particular, does not, and cannot, without changing the fundamental character of the game, have the Unicorn's move( see below).
For example, in 2D chess, a knight at Aa1 cannot reach Ac3 in less than 4 moves. In 3D chess, however, a two-move sequence does it: Aa1 - Bc1 - Aa1.
Check it out! It works.
Pawns move "forward" (towards their side of their home level, which is always one of two directions), and capture bishop-style in 2D diagonals. Thus, a White pawn at Ac2 can move to Ac3 (as in 2D chess) or Bc2 and capture at Ab3, Ad3 (as in 2D chess), or at Bb2, Bd2, and (according to some) at Bc3, although I personally do not like this variant.
Pawns "queen" at their "home row" which for white is the front row of level A and for black is the back row of level E.
Level E a b c d e +----+----+----+----+----+ | BR | BS | BK | BS | BR | 5 +----+----+----+----+----+ | BP | BP | BP | BP | BP | 4 +----+----+----+----+----+ | | | | | | 3 +----+----+----+----+----+ | | | | | | 2 +----+----+----+----+----+ | | | | | | 1 +----+----+----+----+----+ Level D +----+----+----+----+----+ | BU | BB | BQ | BU | BB | +----+----+----+----+----+ | BP | BP | BP | BP | BP | +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ Level C +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ Level B +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ | WP | WP | WP | WP | WP | +----+----+----+----+----+ | WB | WU | WQ | WB | WU | +----+----+----+----+----+ Level A +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ | | | | | | +----+----+----+----+----+ | WP | WP | WP | WP | WP | +----+----+----+----+----+ | WR | WS | WK | WS | WR | +----+----+----+----+----+