Interference is placing a piece on a line between an enemy defender and the square or piece it defends, so the line is cut.
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A long-range defender works along a line. Block that line, and it stops defending, even though it has not moved.
How to do it
- 1Find an enemy bishop, rook or queen defending something from a distance.
- 2Find a square on the line between them that you can reach.
- 3Put a piece there, then take what is no longer defended.
For your level
Interference is easy to miss because the blocking piece often looks loose. Check moves that land between two enemy pieces, not just captures.
Check you have it
Pitch it for:
Question 1 of 2
Play the moves through and count. How much material has the attacker won?
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Question 2 of 2
Which file has no pawns of either colour standing on it?
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Common mistakes
- Blocking a line the defender was not using.
- Missing that the blocking piece can be captured by something other than the defender.
Questions
- What is the difference between interference and blocking?
- Interference blocks a defender's line, so it stops guarding something. Blocking is the wider idea of putting a piece in the way, such as stopping a check or a passed pawn.