Coregal Chess

In 1970, V. R. Parton, inventor of many chess variants, proposed a variant where both the king and queen are royal - and isn't that the way it should be?

Rules

The rules of chess are followed, with the following additions/ modifications:

Just as the king, the queen can be checked and mated. This means that

It is not allowed to make a move such that the queen can be captured.
When your queen is attacked, you must play a move such that the queen is no longer attacked.
You lose the game when your queen is attacked and you cannot make a legal move that avoids the attack.
The rules of check to the king, and mate of the king remain as always.

Queens may move across attacked squares. NOST has used the following additional rules for this variant:

When you promote a pawn to queen, that additional queen also is royal, i.e., subject to check and mate. Thus, underpromotion, e.g., to rook may be in many case a better strategy.
Queens can check kings at a distance, but they cannot check queens.
Kings and queens may castle, both long and short, following usual castling rules.

Comment

Pritchard suggests to forbid queens to pass attacked squares, unless it captures an attacking piece. Optionally, one could play the game without letting queens cross attacked squares at all.

Compare this game with Extinction Chess.

Written by Hans Bodlaender.

WWW page created: 4 Sep 2000. Last modified on: 4 Sep 2000.