Skewer

Reverse Pin Forcing a High-Value Front Target Aside to Capture Behind It

Often called a Reverse Pin, a Skewer attacks a high-value piece (typically the King or Queen) along an open file, rank, or diagonal. Because the front unit is forced to step off the line to save itself, the attacker’s ray continues unobstructed to capture the target standing behind it.

Coach Otto: In open endgames, Otto treats every shared diagonal between your King and Rook as a live wire waiting for an enemy bishop skewer!

Open Anatomical Board Examples & Move Lines

[ARCHETYPE] Skewer (+6.20 Winning) — FEN: 4q3/5p1p/4k1p1/8/8/6P1/3B1PKP/R7 w - - 0 1 · Re1+ Kd7 Rxe8 Kxe8
1. Re1+! — File skewer: checks the exposed King on e6 along the open e-file while aiming straight through to the Queen on e8.
[MASTERPIECE] Long-Diagonal Bishop Skewer (+6.70 Winning) — FEN: 8/8/5p1q/6k1/P7/B4PP1/6K1/8 w - - 0 1 · Bc1+ Kg6 Bxh6 Kxh6
1. Bc1+! — Diagonal skewer from afar: checks the King on g5 and spears the Queen standing directly behind it on h6.

Geometric Preconditions & Board Triggers

An unobstructed rank, file, or diagonal connects your slider, a high-value enemy front unit, and a second target behind it.
The front piece is either the King (absolute skewer via check) or worth substantially more than the attacker.
The attacker itself stands safe on its launching square—or is protected—so the front piece cannot capture it.

Defensive Antidotes & Calculation Pitfalls

Never park your King on the same file, rank, or square-color diagonal as an undefended Queen or Rook.
Check whether an interposing piece can block the check IN FRONT of the King rather than stepping the King aside.
If your King must move off the ray, step diagonally toward the rear piece so your King recaptures the skewering unit if it takes.

FAQ

Why do Skewers happen far more frequently in endgames than in openings?

Once pawn shields thin out, Kings march into the center while Rooks and Queens roam open files and long diagonals—creating frequent unprotected two-piece alignments.

How can a King defend its own skewered Rook on a neighboring square?

If the Rook stands only one square behind the King, stepping the King diagonally adjacent to the Rook keeps it defended—turning a fatal skewer into an equal trade.

Which pieces can execute a Skewer?

Exclusively long-range linear pieces: Queens, Rooks (along ranks and files), and Bishops (along diagonals).

Sister Patterns, Opening Habitats & Grandmaster Links

T02 · Pin (Absolute & Relative) (Immobilizing an Enemy Shield Piece Along a Direct Ray Toward King or Heavy Piece) · T04 · X-Ray Attack (Controlling or Defending a Critical Square Directly Through an Intervening Enemy Piece) · T05 · Discovered Attack (Moving a Shielding Piece with Tempo to Unleash a Hidden Ranged Battery Behind It)