The Chess Variant Pages

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Mutation Chess is also know as FRANKFURT CHESS.

This Variant has been invented in 1986 by John E. Bosley (New Zealand).


The rules of FIDE Chess apply with this change:

The capturing piece turns into the captured piece without changing color, i.e., when a white pawn takes a black rook, the white pawn turns into a white rook.

An unpublished problem of Mutation Chess

Vito Rallo

Helpmate 2 move MUTATION

White(4): Kd3, Rf5, Bc3, Pg2
Black(9): Kd1, Rg1,Rc2, Ba3, Pf2, Pg3, Ph3, Pb4, Pe5

For the solution, contact Vito Rallo (email removed contact us for address)


Mutation is played only like progressive chess. The white begins with one move, the black plays two consecutive moves, white three, and so on. The Olympic champion is Angelo Mapelli (Italy). The leader of ELO Rating is Vito Rallo (Italy).


Mapelli-Fontana (Grand Prix 90) 1-0
2.e5 d5
3.e:d5 d4 d:e5
4.c6 c:d5 f6 f:e5
5.f4 f:e5 Bd3 Qf3 Ke2
6.Bh3 Bg2=P g:h1=R Bc5 Qe7 R:g1=N+
7.Kf1 Be3 K:g1 Kf2 B:c5 Bd6 B:b8=N
8.a5 a4 a3 a:b2 b:a1=R R:b1=N R:b8=B Qe6
9.Qf6 a4 a5 a6 a7 a8=R Ra6 Rd6 Rd8#

Written by: Alessandro Castelli (email removed contact us for address) Problem by Vitto Rallo. Diagram drawn by Hans Bodlaender. Jean-Paul Gerber noted an error in the drawn diagram.
WWW page created: 1996. Last modified: February 28, 2001.