Excalibur Mirage, Руководство пользователя

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An interesting choice. Should Black capture the knight with the d-pawn or the b-pawn? If Black captures with the b-
pawn then White will have a “passed” a-pawn. The a-pawn will not have any enemy pawns to oppose it on its path
to promotion and so Black will need to use his king or one of his knights to keep the a-pawn under observation. If
Black captures on c6 with his d pawn he leaves the pawn on e7 “isolated”, that is to say, it has none of its own pawns
on adjacent files to protect it. But by capturing on c6 with his d-pawn, Black avoids leaving White with a passed
pawn, and although the black e-pawn (on e7) represents a weakness, it is less important than allowing White a passed
pawn. So 7 ... d7xc6 is stronger than 7 ... b7xc6.
After recapturing on c6 Black has won a knight for 3 pawns. In pure material terms a knight is worth roughly the
same as 3 pawns, but in this position White has no passed pawns and none of White’s pawns is any kind of a threat to
Black, so Black has a clear advantage.
KINGS AND BISHOPS
After pressing MODE and seeing TEACH displayed on the LCD, if you press the BISHOP key the computer will
be ready to start play with only the kings and bishops on the board. The bishop is often a mobile piece but it is
important that it does not get hemmed in and even trapped by the enemy pawns. Here is an example of what can
happen from the above position. (If you would like to try this position on the Mirage you can do so by using the
SET UP feature to add your pawns to match the above position.)
1 e 2 - e 4 e 7 - e 5
2 B f l - b 5 a 7 - a 6
3 B b 5 - a 4 b 7 - b 5
4 B a 4 - b 3 a 6 - a 5
Can you see what Black is threatening?
5 d2-d3??
White is anxious to get his c1 bishop into play and completely overlooks Black’s idea. Better moves, for example,
would be 5 a2-a4 or 5 c2-c3.
5 ... a5-a4
6 Bb3-d5 c7-c
White’s bishop on d5 is attacked and has no safe place to go, so White loses a bishop in return for only a pawn.