EChess

The Evolutionary CHESS (micro)

The game was conceived in a train, not long after New Year's Eve, 2016. It was inspired by evolution in Nature. The idea is to refresh chess gaming experience by upgrading promotion, e.g. adding an evolution to the game.

The game has been played many times with friends and is proved to be fun and entertaining. The positions may become very sharp, and creative thinking is usually required.

Setup

Array
(
    [0] => http://www.jinchess.com/chessboard/?p=----k---pppppppp--------------------------------PPPPPPPP----K
)

The game starts only with 8 Pawns and a King of each color on their standard chess positions.

Rules

The game essentially adds only two chess rules.

1. The First Evolutionary Addendum aka "To Minor Piece Promotion"

In addition to chess rules, Pawns may be promoted to minor pieces under the following conditions. After every N = 3 Pawn moves, the player gains the right to promote to a minor piece (a Knight or a Bishop) the last Pawn that moved. The pawn does not necessary need to be promoted, but then the right is lost and the counter N is reset to zero (N = 0).

2. The Second Evolutionary Addendum aka "To Rook Promotion"

After every K = 2 (non-Pawn) opponent piece captures, ANY player's minor piece on the board may be promoted to a rook (even if it wasn't the last piece to move). If there was no minor piece to be promoted, but the capture was made by a Pawn on the third Pawn move (N = 3), the Pawn may be promoted directly to a rook. If there was no "To Rook Promotion", the right is lost for the next K = 2 (non-Pawn) opponent piece captures (i.e. the counter K is reset, K = 0).

Clarifications

• Only one piece at a time can be promoted even if several conditions are met (e.g. capture + Pawn move). Then, the player may choose to promote the Pawn (to a minor piece OR to a Rook) or any of the existing minor pieces (only to a Rook).
• A promotion is available only in the end of the player's move.
• If the 8th rank is reached by a Pawn, the Pawn promotion is obligatory (to a minor piece, Rook or a Queen). No other promotions are possible at that move. The move is normally counted towards the Pawn moves N.
• N = 3 means that there were made three moves by Pawns. Thus, it can be either the same Pawn or different Pawns. The moves do not need to be consecutive: other pieces may be moved between those moves, but only Pawn moves count towards N.
• Capturing moves by Pawns are counted towards both "To Minor Piece Promotion" and "To Rook Promotion".
• Castling is not defined.

Notes

Playing EChess

• A standard chess board usually appears to be enough to play the game. In addition, a piece of paper and a pen make easier to count the Pawn moves and captures, but are not required.
• Hint: to avoid losing a Pawn promotion right, move the King.
• Special thanks to Alexandru T. for helping to make the game balanced.

Last revised by bp .