The game of Leaping Bat Chess, outlined on the preceding page, avoids stereotyped openings by having, as it were, a pre-opening phase involving battles between the short-range pieces on the front rank. However, the large scale of that game changes its character considerably from that of regular Chess, despite my efforts to design the opening array in such a way to retain as many features of regular Chess as possible.
The following diagram:
shows the layout of a form of Chess which involves a far more modest augmentation of the board. The rules are as for regular Chess except that the stalemate rule is as for Leaping Bat Chess (the player forcing stalemate gets 3/5 of the point for the game, the other player getting 2/5), and the King moves four squares when castling to Kingside or Queenside, and the moves of the additional pieces used are as described in the rules of Leaping Bat Chess.
In Checkers, the first few moves of the two players are chosen randomly in an attempt to avoid stereotyped openings. Several proposals have been made to do this for Chess by shuffling the order in which the men are placed on the back rank.
This variant proposes to deal with the problem in a different way, one which retains the symmetry of the opening layout. As you can see in the diagram above, four squares in each player's back rank contain question marks.
Which pieces are to occupy those squares is what is chosen at random in this form of Chess, from the following list of possibilities:
1) Giraffe, Camel; Camel, Giraffe 2) Fers, Camel; Camel, Fers 3) Wazir, Camel; Camel, Wazir 4) Man, Camel; Camel, Man 5) Alfil, Camel; Camel, Alfil 6) Dabbaba, Camel; Camel, Dabbaba 7) Walker, Camel; Camel, Walker 8) Tiger, Camel; Camel, Tiger 9) Rhinoceros, Camel; Camel, Griffin 10) Wazir, Fers; Fers, Wazir 11) Man, Fers; Fers, Man 12) Walker, Fers; Fers, Walker 13) Tiger, Fers; Fers, Tiger 14) Rhinoceros, Fers; Fers, Griffin 15) Man, Wazir; Wazir, Man 16) Walker, Wazir; Wazir, Walker 17) Tiger, Wazir; Wazir, Tiger 18) Rhinoceros, Wazir; Wazir, Griffin 19) Man, Alfil; Alfil, Man 20) Walker, Alfil; Alfil, Walker 21) Tiger, Alfil; Alfil, Tiger 22) Rhinoceros, Alfil; Alfil, Griffin 23) Man, Dabbaba; Dabbaba, Man 24) Walker, Dabbaba; Dabbaba, Walker 25) Tiger, Dabbaba; Dabbaba, Tiger 26) Rhinoceros, Dabbaba; Dabbaba, Griffin 27) Man, Walker; Walker, Man 28) Tiger, Walker; Walker, Tiger 29) Rhinoceros, Walker; Walker, Griffin 30) Tiger, Man; Man, Tiger 31) Rhinoceros, Man; Man, Griffin 32) Rhinoceros, Tiger; Tiger, Griffin 33) Zebra, Camel; Camel, Zebra 34) Zebra, Fers; Fers, Zebra 35) Zebra, Wazir; Wazir, Zebra 36) Zebra, Man; Man, Zebra 37) Zebra, Walker; Walker, Zebra 38) Tiger, Zebra; Zebra, Tiger 39) Rhinoceros, Zebra; Zebra, Griffin 40) Giraffe, Zebra; Zebra, Giraffe 41) Walker, Tiger; Tiger, Walker 42) Man, Tiger; Tiger, Man 43) Zebra, Tiger; Tiger, Zebra 44) Dabbaba, Alfil; Alfil, Dabbaba 45) Man, Fers; Fers, Wazir
In addition to playing each form of Chess thus randomly selected twice, with one player and then the other as White, the schedule of games is also to be varied so that each player has an equal chance of being the first to play a variant.
Thus, four games between two players would proceed in the fashion:
Game 1: A: White B: Black random variant 1 Game 2: A: Black B: White random variant 2 Game 3: A: White B: Black random variant 2 Game 4: A: Black B: White random variant 1
Also, optionally, the first 32 alternatives in the list above can stand on their own as the pool from which to select a variant.
Should, however, 45 possibilities be deemed insufficient, another method of randomizing the variant in use is provided, which offers more variations. Extended Random Variant Chess requires that several more pieces be defined, as follows:
The Empress (also known as the Chancellor) moves as either the Rook or the Knight.
The Princess (also known as the Archbishop) moves as either the Bishop or the Knight.
The Cannon (also known as the Pao) moves as a Rook, but when capturing, must jump over exactly one piece of either color to reach the piece to be captured, on any square beyond it.
The Leo moves as a Queen, but follows the same rule for capturing as the Cannon.
The Vao moves as a Bishop, but follows the same rule for capturing as the Cannon.
The Grasshopper moves, and captures, on the square immediately beyond the nearest piece of either color in any of the eight directions in which a Queen moves. Thus, the eight spaces to which the white Grasshopper in the center of the board in this diagram can move to are those which contain black Grasshoppers.
The Archer moves, but does not capture, as a Man, and captures (and gives check), but does not move without capturing, as a Knight.
The Sprinter moves, but does not capture, as a Giraffe, and captures (and gives check), but does not move without capturing, as a Man: to any immediately adjacent square, diagonally or orthogonally.
The Star moves and captures as either a Wazir or an Alfil; that is, it can move one space orthogonally, or two spaces diagonally.
Given these extra pieces, the choice of a random variant from the larger pool for Extended Random Variant Chess may proceed in one of two ways:
The first method (yielding General Extended Random Variant Chess) begins with this step:
It is chosen at random for the Queen to be replaced by one of:
1) a Queen (that is, left alone) 2) a Griffin 3) a Rhinoceros 4) an Empress 5) a Leo
It is chosen at random for the two Bishops to both be replaced by a pair of:
1) Bishops (that is, left alone) 2) Tigers 3) Sprinters 4) Vaos
It is chosen at random for the two Rooks to both be replaced by a pair of:
1) Rooks (that is, left alone) 2) Princesses 3) Cannons
It is chosen at random for the two Knights to both be replaced by a pair of:
1) Knights (that is, left alone) 2) Men 3) Zebras 4) Archers 5) Stars 6) Grasshoppers
The second method (yielding Restricted Extended Random Variant Chess) proceeds as follows:
A piece substitution is chosen at random from the following list:
1) No substitutions. 2) Griffin replaces Queen. 3) Rhinoceros replaces Queen. 4) Empress replaces Queen. 5) Leo replaces Queen. 6) Tigers replace Bishops. 7) Sprinters replace Bishops. 8) Vaos replace Bishops. 9) Princesses replace Rooks. 10) Cannons replace Rooks. 11) Men replace Knights. 12) Zebras replace Knights. 13) Archers replace Knights. 14) Stars replace Knights. 15) Grasshoppers replace Knights.
Both methods now continue as follows:
Then, one of the 45 variations for the unallotted two positions on each side of the board is chosen. The variation may need to be modified, depending on the replacements chosen for the Queen, the Bishops, or the Knights, as follows:
The first method provides for 16,200 possible opening arrays, all of which largely retain the symmetry and balance of forces of the regular game of Chess. The second method provides only 675 variations.
The first method of producing a random chess variant all but ensures that the ordinary chessmen, other than the King and the Pawns, will not be present. As this is not necessarily desirable, even if more than 45 possibilities are felt to be needed, the second method, which has the advantage that most of the conventional chessmen will still be present was developed. With 675 possible opening arrays, it should still provide sufficient variety to preclude an excessive reliance upon book openings.
Also note that if the Rooks are replaced by Cannons, castling may still take place, with the Cannons functioning as the Rooks, but if the Rooks are replaced by Princesses, there is no castling.
Only one combination of substitutions is chosen, and it applies to both players, just as the variation chosen from among those in the list of 45 variations applies to both players.
Examination of the possibilities offered by the two forms of Extended Random Variant Chess has suggested a third form, based on Restricted Extended Random Variant Chess. In this form, choosing the variant has three steps.
The first step is to choose a base array, from three possibilities involving related pieces:
1) Rook, ?, ?, Knight, Bishop, Queen, King, Bishop, Knight, ?, ?, Rook 2) Rook, ?, ?, Archer, Sprinter, Queen, King, Sprinter, Archer, ?, ?, Rook 3) Cannon, ?, ?, Knight, Vao, Leo, King, Vao, Knight, ?, ?, Cannon
The next step is to choose a substitution at random in the fashion of Restricted Extended Random Variant Chess. If General Extended Random Variant Chess were used, one could use the rule that "leaving the Knight alone" may mean "replacing the Archer by a Knight", and "replacing the Rook by a Cannon" may mean "leaving the Cannon alone". However, then the base array would be irrelevant. Since it is the substitution rule of Restricted Extended Random Variant Chess that is used, the substitutions have to be modified the opposite way to work: if Archers are present, "Replace Knights by Archers" must change to "Replace Archers by Knights", if Vaos are present, "Replace Bishops by Vaos" must change to "Replace Vaos by Bishops", so that all the possibilities of changing one piece in the base array selected remain available.
The third step is to choose one of the 45 variants for the positions noted by question marks.
This version, Systematic Random Variant Chess, allows the most interesting possibilities reachable by the General Extended version to be available, but retains the advantage of the Restricted Extended version of a less haphazard layout. It provides 1,935 possible opening layouts. (The number would be 2,025, except for two duplicate cases; as the second base array differs from the first base array in only two pieces, the combination with a Bishop and an Archer, or a Sprinter and a Knight, can be obtained with either array, and a different substitution in each case.)
Note that if it is considered a problem that some reachable arrangements are more probable than others, this can be solved as follows: consider the arrangements where an Archer or a Sprinter are substituted in from base array 1 as the original, and those where a Knight or a Bishop are substituted in from base array 2 as the duplicate, and make the duplicate arrangements unique by making the additional substitution of a Griffin for the Queen in that case.
As an example of General Extended Random Variant Chess, here is what the array would become if the following random selection of a variant took place:
Queen: 5) Replaced by Leo Bishops: 2) Replaced by Tigers Rooks: 3) Replaced by Cannons Knights: 1) Left as Knights Variant: 32) Rhinoceros, Tiger; Tiger, Griffin
Since the Bishops were replaced by Tigers, the Tigers in the variant are replaced by Vaos, and the pieces on the back rank are:
Cannon, Rhinoceros, Vao, Knight, Tiger, Leo, King, Tiger, Knight, Vao, Griffin, Cannon
as shown in the diagram below:
Note that in this diagram, a circled G replaces the symbol used on the previous page for the Griffin; that makes that symbol available to represent the Leo, to correspond with analogous symbols representing the Vao and the Cannon.
In addition to the conventional promotion rule, that Pawns only promote to pieces found in the initial array for the particular game being played, two alternative promotion rules are advanced as possible options:
Pawns could be allowed to promote only to pieces which, while part of the pool of possible pieces from which a variant could be constructed, were not part of the initial array, subject also to the further restriction that only pieces of types not previously promoted to may be used.
This rule has two results: like promotion to captured pieces, it conserves physical chess pieces, and it further increases the variety of pieces potentially on the board. (Incidentally, note that neither the Bat, nor the Nightrider, two especially "troublesome" pieces, are included in the pool of those used for this variation.)
Alternatively, pawns could be, regardless of the specific variant in use, allowed only to promote to pieces found in the 'base' version of the array: Queen, Rook, Bishop, Knight, Camel, and Giraffe.
This would reduce the confusion that the large variety of possible initial arrays could potentially cause for promotion.
The Grasshopper, originally invented by T. R. Dawson, is one of the most popular Fairy pieces used in problems. I have given names to the Archer, Sprinter, and Star, but these are all such trivial combined pieces that they are unlikely to be original. The other pieces introduced on this page are well-established pieces used in Fairy Chess problems.