Yangsi

When I first stumbled upon the Chess Variant Pages back in 2016, it was due to an image of a large chess variant I encountered while looking at images of chess variants. The image I found was a picture of Fergus Duniho's Gross Chess, an expanded version of chess played on a 12x12 board with a wider assortment of pieces. Shortly after that, my interest in the site started to grow, as did my interest in chess variants in general. I also started to invent my own chess variants. I started by placing the 12 different pieces from Gross Chess onto a 10x10 board and making a few small changes to the rules to make the game more similar to FIDE Chess, giving birth to the game of Yangsi.

Play Yangsi with others or against an AI via Ai Ai

Play Yangsi against others via Game Courier

Setup

An interactive diagram has been provided (The Javascript source code was written by H. G. Muller) to make it easier to understand how each piece moves. The diagram uses pieces from the Musketeer Chess Board Painter.

First rank

• a1, j1 Marshall (RN)
• b1, i1 Wizard (FC)
• c1, h1 Cannon (mRcpR)
• d1, g1 Archbishop (BN)
• e1, f1 Vao (mBcpB)

Second rank

• a2, j2 Rook (R)
• b2, i2 Champion (WAD)
• c2, h2 Knight (N)
• d2, g2 Bishop (B)
• e2 Queen (Q)
• f2 King (KisO3isO2)

Third rank

• a3-j3 Pawns (ifmnDfmWfceF)

M/m = Marshall, A/a = Archbishop, V/v = Vao, W/w = Wizard, C/c = Cannon,
R/r = Rook, S/s = Champion, N/n = Knight, B/b = Bishop, Q/q = Queen, K/k = King, P/p = Pawn

Pieces

King	The King moves one space in any direction but not into check. It moves the same as it does in Chess but castles differently.	Queen	The Queen moves as a Rook or a Bishop, the same as it does in Chess.
Marshall	The Marshall moves as a Rook or a Knight. It is a popular piece in many Chess variants, dating back centuries, even before Chess as we know it today came into existence.	Archbishop	The Archbishop moves as a Knight or a Bishop. It is a popular piece in many Chess variants, dating back centuries, even before Chess as we know it today came into existence.
Rook	The Rook slides across the board in a vertical or horizontal direction, as it does in Chess.	Bishop	The Bishop slides across the board in any diagonal direction, as it does in Chess.
Knight	The Knight leaps to a space one file and two ranks away or two files and one rank away, as it does in Chess.	Pawn	The Pawn moves one space vertically forward without capturing, and it moves one space diagonally forward to capture, as it does in Chess. It can also move two squares forward on its first move and capture by en passant a Pawn that has just made a double move like it does in Chess. However, it is subject to different rules of promotion.
Champion	The Champion leaps two spaces in any orthogonal or diagonal direction, or one space in any orthogonal direction. It is a compound of the Alfil, Dababbah, and Wazir. It was introduced in Omega Chess, and it moves the same as it does in that game.	Wizard	The Wizard moves one space diagonally or leaps to a space one file and three ranks away or three files and one rank away. It is a compound of the Ferz and the Camel. It was introduced in Omega Chess, and it moves the same as it does in that game.
Cannon	The Cannon moves as a Rook but must hop over an intervening piece to capture. This piece comes from Chinese Chess and moves the same as it does in that game.	Vao	The Vao moves as a Bishop but must hop over an intervening piece to capture. It was created in the early 20th century as the diagonal counterpart to the Cannon.

Rules

Aside from differences in the board, pieces, and setup, Yangsi is played like FIDE Chess with the following differences:

Pawn promotion: When a Pawn reaches the last rank, it must promote to another piece of that player's choice: a Queen, Marshall, Archbishop, Rook, Champion, Cannon, Knight, Bishop, Vao, or Wizard of the same color. It cannot promote to King or another Pawn.

Castling: When castling, a King may move two or three spaces toward the Rook when it castles, with the Rook leaping over the King to the closest space the King has just passed over, so that King and Rook end up adjacent to each other. The usual castling conditions from Chess apply. A King may not castle from or through check, all spaces between the Rook and King must be empty, and neither piece may have moved before.

64-move rule: The 50-move rule from Chess becomes a 64-move rule in Yangsi. Similarly, the lesser-known 75-move rule from Chess is a 96-move rule in Yangsi.

Notes

Similar Games

• Hectochess
• Ryugi

Assorted Yangsi Problems

ZIP Folder w/ Pictures, FEN Codes, Conditions, and Solutions

Sufficient mating material

An important factor in determining the outcome of the game is whether a player has enough material checkmate the enemy King. The most important aspect of determining this is the distinction between major and minor pieces.

The Queen, Marshall, Archbishop, Rook, and Champion are all major pieces. A single major piece that hasn’t been captured is sufficient mating material because it can checkmate a lone King with the help of its own King.

The Cannon, Knight, Bishop, Vao, and Wizard are all minor pieces. A single minor piece is insufficient mating material because the minor pieces do not have the checkmating capabilities that the major pieces have. However, another factor to consider is what combination of two minor pieces constitutes sufficient mating material. This is worth putting into a table.

A lone King is insufficient mating material because the King cannot move into check. A single Pawn is sufficient mating material due to the promotion rule, provided that it promotes to a major piece.

Thoughts on the rules

Pawn promotion: In Chess, Pawns can promote to any piece that is not a pawn or King. I carried this rule over to Yangsi without altering the meaning of the words used, allowing for a wider range of choices.

Castling: Because of  the larger board size, I decided to allow the King to move two or three spaces when castling, as this allows the king to get to the side of the board faster than if normal castling is used. I also allowed normal castling to allow for more opening variations.

64-move rule: I changed the 50-move rule to a 64-move rule based on the principle that if each of the board's dimensions is multiplied by n, the number of non-capturing or non-pawn moves allowable before draw claims become possible must also be multiplied by at least n. I also changed the 75-move rule* to a 96-move rule based on the same principle.

Threefold Repetition: I decided to adopt this rule and its lesser-known fivefold repetition counterpart** for Yangsi without altering them at all, as there wasn't any need to be change them.

*The 75-move rule is a lesser-known rule in Chess which is closely linked to the 50-move rule. It states that if no pawn has been moved and no capture has been made in the last 75 moves by each player, then the game is automatically a draw, which means that a player does not have to claim a draw for the rule to be invoked.

**The fivefold repitition rule is a lesser-known rule in Chess which is closely linked to the threefold rule. It states that if the same board position occurs five consecutive times, then the game is automatically a draw, which means that a player does not have to claim a draw for the rule to be invoked.

Last revised by A. M. DeWitt.