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This page is written by the game's inventor, Jose Carrillo.

# Contemporary Random Chess

Contemporary Random Chess (CRC), which was formerly called Modern Random Chess 64, was an accidental invention based on the adaptation of some of the 'Modern' principles from my 9x9 Modern Random Chess (MRC) game to a standard 8x8 board.

CRC inherits from Modern Random Chess the random setup (including the option of having both Bishops start up on squares of the same color), reverse symmetry, symmetric castling to either side, and the Bishop Adjustment Rule.

## Setup

.... ....

All pieces are randomly placed in the playerâ€™s first rank, with the only restriction that the King must be between the two rooks. It is possible for both Bishops to be on the same color squares (dark or light squares). The opponentsâ€™ pieces are placed with reverse symmetry (Whiteâ€™s piece at a1 is equivalent to Blackâ€™s h8, Whiteâ€™s b1 to Blackâ€™s g8, Whiteâ€™s c1 to Blackâ€™s f8, Whiteâ€™s d1 to Blackâ€™s e8, and so onâ€¦)

There is a Bishop Adjustment rule that is in effect only in games when both Bishops start on the same color squares in the initial random setup. This rule allows players to move one of the Bishops to the opposite color, if they so desire.

There are 1,680 different legal starting positions in Contemporary Random Chess.

## Reverse Symmetry

In a reverse symmetrical setup the piece at the square a1 for White, is the same as the piece at h8 for Black. The piece at b1 for White is the same as the one at g8 for Black, and so on. The Pawns are in the second row of each playerâ€™s side.

Let looks at another example, from both White and Blackâ€™s point of view:

....

In the CRC position on the left, from Whiteâ€™s point of view, the Queen is on the leftmost square next to a Rook, his 2nd Rook is on his rightmost square next to a Knight, the Bishops are on their traditional Orthodox Chess initial squares, the King has a Knight to his right, and so on. Also, from Whiteâ€™s point of view, his opponentâ€™s opponents King is across the board from the Knight to his right, the Bishops are across the board to each other, the Queen is on the other corner of the same long diagonal as his own Queen, and you could continue to describe the position of the opponentâ€™s pieces in relation of Whiteâ€™s own.

Now look at the same CRC position in the diagram on the right, but from Blackâ€™s point of view. Every single observation made from Whiteâ€™s point of view above, applies as well to the point of view from Black. That's reverse symmetry!

## Pieces

Orthodox Chess pieces are exclusively used.

## Rules

Orthodox Chess rules apply when applicable. Modified Castling rules are below, as well as the new Bishop Adjustment Rule.

### Castling

The Contemporary Random Chess castling rules are based in the Fischer Random Chess rules.

In CRC, depending on the pre-castling position on the castling King and Rook, the castling manoeuvre is performed by one of these four methods:

• Double-move castling: By on one turn making a move with the king and a move with the rook.
• Transposition castling: By transposing the position of the king and the rook.
• King-move-only castling: By making only a move with the king.
• Rook-move-only castling: By making only a move with the rook.

Castling the King and Rook will be placed as if the player had castled short in Orthodox Chess, both to either side of the board. There is no long castling (O-O-O) in CRC.

Thus, after b-castling (notated as O-Ob), the King is on the b-square (b1 for White and b8 for Black) and the Rook is on the c-square (c1 for White and c8 for Black). After g-castling (notated as O-Og), the King is on the g-square (g1 for White and g8 for Black) and the Rook is on the f-square (f1 for White and g8 for Black). g-castling (O-Og) is identical to Ortodox Chess short castling (O-O).

This table shows where the King and Rook end up and the notation for each type of castling.

White castles a-side White castles h-side Black castles a-side b-castling O-Ob Kb1, Rc1 g-castling O-Og Kg1, Rf1 b-castling O-Ob Kb8, Rc8 g-castling O-Og Kg8, Rf8

However, castling may only occur under the following conditions, which are extensions of the standard rules for castling:

• Unmoved: The King and the castling Rook must not have moved before in the game, including a previous castling or a Bishop Adjustment.
• Un-attacked: All of the squares between the king's initial and final squares (including the initial and final squares) must not be under attack by any opposing piece.
• Vacant: All the squares between the king's initial and final squares (including the final square), and all of the squares between the rook's initial and final squares (including the final square), must be vacant except for the king and castling rook.
These rules have the following consequences:

• Castling cannot capture any pieces.
• The king and castling rook cannot "jump" over any pieces other than each other.
• A player may castle at most once in a game.
• If a player moves his king or both of his initial rooks without castling, he may not castle during the rest of the game.
• In some starting positions, some squares can stay filled during castling that would have to be vacant in Modern Chess. For example, after c-castling (O-Oc), it's possible for to have a, b, and/or e still filled, and after g-castling (O-Og), it's possible to have e, h and/or i filled.
• In some starting positions, the king or rook (but not both) do not move during castling.
• In some starting positions, castling can take place as early as the first move.
• The king may not be in check before or after castling.
• The king cannot move through check.
• The king cannot jump over his own rook if and when said rook stands on a â€œcheckedâ€ square.
• A King that has swapped places with a Bishop according to the Bishop Adjustment rule can no longer do castling for the rest of the game.
• A Rook that has swapped places with a Bishop according to the Bishop Adjustment rule can no longer castle with the King.
• Castling in CRC is symmetric to either side of the board. CRC Castling is like the Orthodox short castling (O-O) but to either side.

### King's Bunker Leap

Contemporary Random Chess introduces the King's Bunker Leap to the realm of Modern variants. The 'King to Bunker Leap' proposed by Charles Daniel in 2009, blends very well with the Modern variants' symmetrical castling.

Basically the rule boils down to this: During the course of play, either side can move the king from their initial square to the square they would have landed after castling, by jumping over any friendly pieces if necessary.

The move can be carried out once per game, it takes a turn and is subject to similar restrictions to those in castling. The main difference is that a rook is not involved in the play and the King can make a one-time jump.

Instead of castling, a side can carry out the King's Bunker Leap, by moving from its initial square to the bunker squares on the b or g file (i.e. b1 or g1 for White, b8 or g8 for Black).

The King's Bunker Leap may only occur under the following conditions:

• Unmoved: The King must not have moved before in the game, including a previous Bunker Leap, Castling or a Bishop Adjustment.
• Un-attacked: All of the squares between the King's initial and final squares (including the initial and final squares) must not be under attack or occupied, by any opposing piece.
• Vacant: The King's final square must be vacant.
These rules have the following consequences:

• The King's Bunker Leap cannot capture any pieces.
• The King can only "jump" over friendly pieces.
• A player may do the King's Bunker Leap at most once in a game.
• If a player moves his King without doing a Bunker Leap, he may not do it during the rest of the game.
• The King may not be in check before or after a Bunker Leap.
• The King cannot jump through check.
• A King that has previously castled, or swapped places with a Bishop according to the Bishop Adjustment rule, can no longer do a Bunker Leap for the rest of the game.
The algebraic notation for the King's Bunker Leap in the Modern variants is:

Kx>>yy

Where x is the departure square for the King, '>>' stands for 'Bunker Leap' and yy is the destination bunker square (b1, g1, b8, g8)

Example: Kc>>g1 stands for a King to bunker leap from c1 square to g1.

### The Bishop Adjustment Rule

In those positions where the Bishops start up in the same color squares (either both on dark or light squares), players on their turn, are allowed to convert one (and only one) of their Bishops to the opposite color square by swapping places with any piece adjacent to them. Neither the Bishop nor the piece to be adjusted with may have moved before the Bishop swap. The Bishop adjustment will count as a single turn, and a move for both the Bishop and the piece swapped with.

The Bishop Adjustment Rule is optional, and a player is not forced to use it. A player may choose to play with his Bishops on the same color squares if he so desires, even if his opponent chooses to adjust one of his Bishops.

Note that the Bishop Adjustment rule has the following consequences in CRC:

• A Bishop on a corner may only adjust with the one piece adjacent to it.
• The Bishop is allowed to swap places with a Knight, the Queen, a Rook, and also with the King!
• If the Bishop Adjusts with a Rook, that rook will be considered to have moved, and King Castling with that rook will no longer be possible. King Castling with the other Rook will still be possible provided neither the second Rook nor the King have moved.
• If the Bishop Adjusts with the King, the King will be considered to have moved, and neither castling nor the King's Bunker Leap will be available for the rest of the game.
• When adjusting with the King, the Bishop Adjustment is considered to be a â€œBishopâ€ move, and not a King move that enables a player to move out of check. If the King is in check, it is not legal to move out of check with a Bishop Adjustment.

### Sample Bishop Adjustment

Carlos Cetina (MEX) - JosÃ© Carrillo (CAN)
CV Game Courier, May 2008

After 1.e4 e5 2.c3 Be<=>R 3.Bf<=>N c5 (diagram above right)

## Notes

Contemporary Random Chess (CRC) was created by JosÃ© Manuel Carrillo-MuÃ±iz, from Puerto Rico in 2008.

## Game Courier Preset

Contemporary Random Chess

## Game Courier Logs

Game Courier Logs for Games of Contemporary Random Chess

To see actual games that have been played on-line, follow the link above.

## Other Pages by the Author:

This 'user submitted' page is a collaboration between the posting user and the Chess Variant Pages. Registered contributors to the Chess Variant Pages have the ability to post their own works, subject to review and editing by the Chess Variant Pages Editorial Staff.

By Jose Carrillo.
Web page created: 2008-05-16. Web page last updated: 2008-05-16﻿