Undermining
Undermining (also known as removal of the guard, or removing the defender) occurs when a defensive piece is captured, leaving one of the opponent's pieces undefended or under-defended.
The opponent has to choose between recapturing or saving the undefended piece.
Time to practice! White to move and win.
Answers in the next section
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1. Bxb5
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2. _____
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3. _____
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4. _____
Answers
Bxb5
RxBd7
d4xe5
Nb6