Patricia

Dutch gamer Rob Nierse wrote me that he enjoys playing small chess variants. He also invented a small chess variant himself, and wrote me that he likes the game, although games do not take long (they are finished within half an hour.) He called the game Patricia, after his wife. The game was invented in 1996.

See also:

• Alfred Pfeiffers page on Patricia.

Rules

The game is played on a checkered 5 by 5 board. The corners are black, thus there are 13 black, and 12 white squares. Each player has one royal piece, two officer-pieces, and two pawns.

One can use normal chess pieces, but it is better to use flat pieces, like shogi pieces: a possible way is to take checkers (draughts) pieces, and glue pictures of chess pieces at the flat sides. As taken pieces can be dropped as reinforcements, like in Shogi, it would be best to make the wedge-shaped pieces as in shogi, and to distinguish white and black by the direction of the wedge, and not by color.

The royal piece has a king at one side, and a queen at the other side. The officer-piece has a rook at one side, and a bishop at the other side. The pawn piece has a pawn at one side, and the other side is a knight.

Opening setup

The opening setup is as follows:

White:
King c1; Bishop b1, d1; Pawn b2, d2.

Black:
King c5; Bishop b5, d5; Pawn b4, d4.

Movement

White starts. All pieces move and take as in usual chess. However, when a piece is moved, it is turned around, and the other side comes on top. This means, for instance, that when a bishop has moved, it becomes a rook, and when the rook has moved again, it becomes again a bishop, etcetera. The pawn is an exception. When a pawn moves, it stays a pawn; it can become a knight by promoting. The pawn may only move one square forwards, not two, from its opening setup.

For instance, white can start with K c1 - c2: the king becomes a queen, and checks the black king. White can move B d5-c4, the bishop becomes a rook and checks the white royal piece (now a queen).

Dropping pieces

Pieces taken from the opponent do not disappear, but can be parachuted or dropped black into the game, comparable to the rules of shogi. A piece is dropped in the form it had when it was taken: when a rook is taken, the piece is dropped as a rook, and when a bishop is taken, the piece is dropped as a bishop. A consequence is that a promoted pawn never becomes a pawn again.

It is allowed to give mate by dropping a piece; one may not drop a pawn on the last row (from where it would not be able to move further).

Promotion

Pawns promote on the last or one-but last row. When a player moves a pawn to the 4th row, he may choose whether or not he promotes the pawn to a knight. When the pawn is moved to the 5th row, the pawn must be promoted to a knight. When a pawn is dropped to a square on the 4th row, the pawn does not promote on that turn; i.e., a pawn is only promoted after a normal move with it.

Purpose of the game

The purpose of the game is to take the royal piece of the enemy. Thus, it is legal (but not desirable) to move ones royal piece to a square where it can be taken by the opponent. However, sometimes, this would be the only possible move, and thus the player loses, unless his opponent is stupid enough not to take the royal piece.

Rob Nierse wrote that stalemate does not exist. However, this is actually not entirely true, as a position where a player cannot make a move can be constructed, but it is very unlikely that such a position would be formed in a normal game (i.e., it is possible to reach a stalemate position when both players cooperate to arrive at such a position.) Note that a stalemate also means there even is no move with the royal piece (king or queen) where this piece moves to a square that is attacked. See the Patricia Stalemate Puzzle.

In a later letter, Rob stated that a stalemate, in such a special case, is a draw.

Optional rules

The following, optional rules, are not playtested. For variations to this game, one can use one or more of these optional rules.

1. A pawn becomes a knight when moved, and a knight becomes a pawn after moving. Pawns do not promote and a knight moved to the last row becomes immobile.
2. When dropping a piece, one may choose which side is up; this no longer depends on the type of the piece when taken.
3. A king stays a king after moving and never becomes a queen.