The X-Ray Attack
Seeing Through the Obstacles
Usually, we think of pieces as blocking each other. But in an X-Ray, the blocking piece is just a temporary ghost. A famous example involves a "hidden" checkmate threat by Paul Keres.
Paul Keres vs. Alexander Kotov
Parnu (1947) • Sicilian Defense
1. The X-Ray Vision
The Situation: White's Queen on d1 seems blocked by the Black pawn on d6.
The Hidden Truth: Keres realized his Queen was actually X-Raying the square d8. If the d6 pawn moves, Qd8 is Checkmate!
Kotov (Black) felt safe because his pawn on e5 was supported by the d6 pawn. This was a fatal illusion.
2. The Collapse
The Move: 20. Nxe5! (Black Resigns)
White captures the e5 pawn. Black cannot recapture!
- If ...dxe5 (taking the Knight), the d-file opens, and the White Queen flies through to Qd8# (Mate).
- Meanwhile, the White Knight on e5 now attacks Black's Queen on c6.
- The Black Queen has no safe squares. Keres crushed Kotov's position in one move.
From the Archives
"Kotov's tree of analysis must have completely collapsed here."
— Kingscrusher
"Tactics don't just work against pieces. Today's puzzle shows tactics working against **squares**. The d6-pawn was pinned not to a piece, but to the d8 square."