X-ray attack
Attack through a piece to threaten what lies behind (piece, passed pawn, mating square).
X-ray attack
Long-range pieces target a piece or square behind another. Pressure exists even if a front piece blocks temporarily.
X-ray on the d-file
8
7
6
5
4
3
2
a1
b
c
d
e
f
g
h
- d1: X-ray rook
- d5: Blocking piece
- d8: Rook target
Key ideas
Threaten what sits behind the blocking piece, often setting up a skewer or capture on the same file/diagonal.
- Prepare a skewer if the blocker moves
- Pressure on a passed pawn supported by a rook
- Combine with fork or deflection
Open lines
Trade or sacrifice to open the file/diagonal.
- Pawn trades on the target file
- Rook behind a passer for x-ray on promotion square
- Bishop on long diagonal versus a weakened castle
Defending
Relieve x-ray pressure by exchanging the back piece or inserting a sturdy blocker.
- Interpose a well-defended piece
- Close the line with a pawn push
- Trade the rook/bishop applying the x-ray
Training
Train straight-line vision to automate the motif.
- 10 x-ray/skewer puzzles daily
- Look for under-defended blockers
- Compare lines before/after an exchange