# Rules Extensions for Chess Variants

In an email to Hans Bodlaender, Hans Aberg wrote,
A long time ago, I was interested in chess variations; for example, I made a chess-for-four players, which I played with my friends. My rating in tournamentchess was about 2000.

I discovered some possible chess rules, which I thought I should make you aware of. The purpose of each of these rules is the same, increase the material and the capacity of the moves, so as to giving the game more structure. The game should then be normally be shorter.

## Suggested Rule Changes

• Extended pawn rule: An alternative way to phrase the rules for pawns in current chess is that when it is before the third rank, the pawn can move two steps. En passant rules apply when moving the pawn two steps.

One could extend this say by saying that when a pawn has not yet reached the fourth rank, it can move two steps. Pawn then become more active in the earlier parts of the game. Further, on a board more than eight deep (such as the one for four players), it is needed, otherwise the paws become too slow.

• Extended castling rule: The disadvantage with the current castling rule is that it favours the king's side castling over the queen's side castling in view of the extra preparatory moves one must often make. So the idea of this rule is to eliminate the need of such extra preparatory moves.

The rule:

1. The king or the castling rook must not have made a move before.
2. The squares between the king and the castling rook must be empty.
3. The king's original square, the squares that the king move over, and the square where it finishes must not be threatened by any of the opponents pieces.
4. The king may move to any of the squares between the king's original position and the castling rook's original position.
5. The rook may move to any of the squares that the king has moved over, or the original square of the king.

• Alternatives with the respect to the Capablanca's chess rules:

a. I think that one should perhaps put the piece that can move both as a rook and a knight on the queen's side. The reason is that this piece will be weaker than the one that moves as a rook and a bishop, and the queen's side already has more material than the king's side. One might still call the queen's side piece the archbishop and the king's side piece the chancellor, though.

b. I think that perhaps that the knight should be put adjacent to the bishops, which in their turn adjacent to the queen and the king. The reason is that the knights become weaker towards the sides of the board, and therefore should be put more towards the center. Thus the board would be:

```Black: Rook Archbishop Knight Bishop Queen King Bishop Knight Chancellor Rook

Pawn   Pawn     Pawn   Pawn   Pawn  Pawn  Pawn   Pawn   Pawn      Pawn

.      .        .      .      .     .     .      .      .         .

.      .        .      .      .     .     .      .      .         .

.      .        .      .      .     .     .      .      .         .

.      .        .      .      .     .     .      .      .         .

Pawn   Pawn     Pawn   Pawn   Pawn  Pawn  Pawn   Pawn   Pawn      Pawn

White: Rook Archbishop Knight Bishop Queen King Bishop Knight Chancellor Rook

```

I think that a 10 ten deep board defeats the purpose of making the game faster and more strategic, so I think that one should work only with the eight deep board (thus the same reason that made Lasker and Capablanca switch to an eight ranks deep board).

But I think that only experimentation by good strength player could actually tell what the rules ought to be.

It would be fun to see a chess such as the MacChess by Wim van Beusekom <(email removed contact us for address) ware.nl> extended to some form of Capablanca's chess.

```  Hans Aberg
* Email: Hans Aberg <mailto:(email removed contact us for address) ber.ams.org>