Editing Newsletter/Summer 2008 (section)

== Three Dimensional Chess ==
by [[Frank Truelove]] a.k.a. [[Lanista]] on [[Mithrandir]]

This article assumes familiarity with normal chess. What follows is 3D-Chess specific.


'''The Boards(s)'''

There are 7 separate boards.
3 (main) 4×4-square boards (Even-numbered Levels)
[[Image:Figure 1.JPG|250px|thumb|left|Seven separate boards are used in 3D Chess. The 4 smaller boards are moveable while the 3 larger boards are stationary]]4 (moveable) 2×2-square boards (Odd-numbered Levels)
The ranks are numbered 0-9 and the files designated a-f. The boards overlaps when taken together as one playing surface, and the 3D chessboard is similar to a staircase with gaps. Control of the moveable boards to bridge the gaps becomes crucial during play. 



'''Move Notations in 3 Dimensions'''

In notation for a game played, vertical position is designated by a number from 1-7, counting up from the bottom, with 1 being on an inverted moveable board suspended from White’s starting area and 7 being a moveable board positioned above Black’s setup zone. This 'altitude' indicator comes after the normal notation of piece/starting square/destination square. Some rules place the vertical position number in brackets or parentheses.


'''Relocation of Moveable Boards'''

Since it is impossible to move directly from one fixed board to the next, play requires mastering the tactics of control of the moveable boards. Think of them as 4-man shuttlecraft. Gaining control of them, and positioning them properly to facilitate an attack on your opponent’s King is what sets the strategy of this version of chess apart from that of the original game.

You begin play as the controller of the 2 moveable boards that start on your setup board. You can gain control of an opponent's board by occupying it uncontestedly. (Moveable boards that are vacated voluntarily remain controlled by their most recent controller.)

Moving a moveable board counts as a move. A player cannot move a piece and a moveable board at the same time unless the piece is a pawn on the board moved.

To transfer a moveable board to a new peg, the player must not be left in check by the move, and the moveable board to me relocated must either have only 1 of the player's own pawns on it or be empty of pieces.

A moveable board (occupied by a pawn or not) may move 1 'step' along a main board edge to another peg on the same main board. It may not be moved to the diagonally-opposite corner of that main board. 

A vacant moveable board can be switched to the opposite end (top or bottom) of the same peg. This means a moveable board placed on the dorsal side of a main board may be moved to the ventral side, and vice versa.

A vacant moveable board can be moved to the board corner directly above or below the moveable board's present location. A moveable board on the top of a lower main board may be moved to the bottom of the next highest main board. A moveable board on the bottom of a higher Main board can be moved to the top of the next lowest Main board.

The peg-positions where moveable boards may be placed are referred to as King’s Level or Queen’s Level and further designated by a number, as in "Queen's Level 3." Each peg is designated by which side of the board it is on (King’s side or Queen’s side). King's Side and Queen's Side pegs are numbered (see Figure 2). 

Obviously, a moveable board cannot be placed where there already is 1, though a moveable board above and below the same main board can share the same peg (top/bottom).
[[Image:3D Chess Figure 2.JPG|300px|thumb|right|The board and the labels of pegs for the moveable boards]]

'''Movements of the Chess Pieces'''

Pieces are moved in exactly the same when as in normal chess, with 1 exception: after an orthodox chess move, the piece may (as part of the same move) go up or down to a different level, above or beneath the destination square. This effectively means that if there is a space in play above or beneath the destination square, the piece moved can end up on any level up or down from the final square on the board level the move is initiated on. Provided there is a contiguous ‘chain’ of open levels above or below, this would allow moving more than one level vertically. Access to levels is determined by the positions of the moveable boards. It is impossible to move from Level 1 to Level 7 in one uninterrupted movement.

The horizontal component of the move must be executed first. A piece cannot be moved vertically first.

Pieces may be on the same square but on different levels. A piece in a given vertical column serves as a block to movement through that space.


'''Castling'''

Castling is a special move of the King. It may be done to either side. King’s side castling is a simple transposition of the king and the rook next to it. Queen’s side castling requires that the Queen’s stating space be vacated beforehand. The king is moved to the Queen’s initial square and the Queen’s Rook is move to the King’s starting place.

In either case, even though 2 pieces are moved, castling is considered 1 move. Castling may not be performed if the King is in check, or would move into check. (In normal chess, the king cannot move through check either. But because castling in this version takes place on the moveable boards, this isn’t an issue.) Neither the king nor the rook to be castled with may have been moved before this is done. If the king and both rooks have been moved, castling ceases to be an option. Castling cannot be made as the first move of the game either.


'''Trivia'''

3D Chess appears or is mentioned in the following 21 episodes:
TOS ''By Any Other Name''; "Charlie X"; "Court Martial"; "Day of the Dove"; "The Corbomite Maneuver"; "Where No Man Has Gone Before"; "Whom Gods Destroy"
TNG: "Conundrum"; "Galaxy's Child"; "Lower Decks"; "Ménage à Troi"; "Pen Pals"; "Q Who"; "Suddenly Human"; "The Nth Degree"; "The Price"; "Unnatural Selection"
DS9: "Dramatis Personae"; "Statistical Probabilities"; "The Homecoming"
ENT: "In a Mirror, Darkly, Part II"


'''Acknowledgments'''

In this article, depictions of boards and pieces were prepared by me and, as such, are original work.  
I have drawn primarily from the Chess Variant Pages http://www.chessvariants.org/3d.dir/startrek.html and Memory Alpha http://memory-alpha.org/en/wiki/Three-dimensional_chess. 
Andrew Bartmess http://my.ohio.voyager.net/~abartmes/tactical.htm seems to be the originator of these rules.