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Bosma chess

In 1993, Dutch chess problem composer R. Bosma noted in the FIDE-rules article 9.1, which stated:

The King is in check when the square on which it is standing is attacked by one or two enemy pieces.
Thus from this rule, it appears that a king is not in check when its square is attacked three or more times. This inspired Bosma to the following fairy chess form, called Bosma chess:
A king that is attacked three or more times is not considered to be in check.
The rule is used in some fairy chess problems; in actual games, there would be little difference with standard chess.

A problem

Henk Le Grand, the Netherlands
1st Price 151th Thematoernooi
Probleemblad 1993



Bosma Chess. White to mate in two moves.



The information on Bosma chess and the problem are from the book Probleemcomponisten XIII, Henk Le Grand, Piet le Grand, a book by the Nederlandse Bond van Schaakprobleemvrienden on the two Dutch chess problem composers Henk and Piet Le Grand. It is written there:
The FIDE rules have since been adjusted.

Written by Hans Bodlaender. Web page posted by Hans Bodlaender.
WWW page created: 17 Aug 2000. Last modified on: 17 Aug 2000.