Windmill

Relentless Seesaw Machine Alternating Direct Rook Checks and Discovered Bishop Checks

A Windmill (or Seesaw) is a devastating perpetual-tempo harvesting machine built from a Rook on the 7th rank and a Bishop aimed at the cornered enemy King (typically Rg7 + Bf6 vs Kg8/Kh8). By alternating direct Rook checks on g7 with discovered Bishop checks along the 7th rank or g-file, the Rook devours piece after piece for free.

Coach Otto: Before pulling the final exit lever of a Windmill, Otto checks EVERY edible piece along the 7th rank so not a single free snack gets left behind!

Open Anatomical Board Examples & Move Lines

[ARCHETYPE] Torre vs Emanuel Lasker, Moscow 1925 (Climax) (+6.55 Winning) — FEN: r3rnk1/pb3pp1/3ppB1p/7q/1P1P4/4N1R1/P4PPP/4R1K1 w - - 0 26 · Rxg7+ Kh8 Rxf7+ Kg8 Rg7+ Kh8 Rxb7+ Kg8 Rg7+ Kh8 Rg5+ Kh7 Rxh5
26. Rxg7+! — Starts the most celebrated Windmill in chess history! Black’s King is forced into h8.
[MASTERPIECE] Torre vs Lasker, Move 25 Queen Sacrifice Ignition (+6.73 Winning) — FEN: r3rnk1/pb3pp1/3pp2p/1q4BQ/1P1P4/4N1R1/P4PPP/4R1K1 w - - 2 25 · Bf6 Qxh5 Rxg7+ Kh8 Rxf7+ Kg8 Rg7+ Kh8 Rxb7+
25. Bf6!! — Leaves White’s h5 Queen completely undefended to bolt the windmill bishop onto f6!

Geometric Preconditions & Board Triggers

Your Rook reaches g7 (or b7/g2/b2) supported by a long-diagonal Bishop (such as Bf6 or Bb2) pointing straight through g7 at h8.
The enemy King is trapped in a two-square pendulum (g8 ↔ h8) with zero pieces able to capture your Bishop or block the diagonal.
Often ignited by a bold Queen sacrifice (like Torre’s 25. Bf6!! Qxh5) because the Windmill wins the Queen right back with interest!

Defensive Antidotes & Calculation Pitfalls

Guard g7 at all costs whenever an enemy dark-squared bishop reaches f6 or b2!
Trade off or challenge the long-diagonal bishop (...Nd7–f6 or ...Be7xf6) before an enemy rook lifts to the g-file.
Keep a defensive piece able to interpose on g7 or capture the f6 bishop during the discovered check.

FAQ

Why is Carlos Torre vs Emanuel Lasker (Moscow 1925) the canonical Windmill game?

Playing against former World Champion Emanuel Lasker, 20-year-old Mexican prodigy Carlos Torre uncorked 25. Bf6!!, sacrificing his Queen to sweep two pawns, a bishop, and Lasker’s Queen back via six consecutive seesaw checks!

Can two Knights or a Rook + Queen also create a Windmill?

Mostly it requires Rook + Bishop (orthogonal pivot + diagonal unmasking), though Bobby Fischer’s 1956 “Game of the Century” against Donald Byrne featured a celebrated Knight + Bishop discovered-check windmill!

In what exact order should you capture targets during a Windmill?

Gobble every stationary target along the 7th rank FIRST while repeating Rg7+, and save your exit check (such as Rg5+ attacking the enemy Queen on the 5th rank) for the very last rotation!

Sister Patterns, Opening Habitats & Grandmaster Links

T05 · Discovered Attack (Moving a Shielding Piece with Tempo to Unleash a Hidden Ranged Battery Behind It) · T06 · Double Check (Unstoppable Simultaneous Check Along Two Intersecting Vectors Forcing King Flight) · M03 · Blind Swine Mate (Two Connected Rooks Rampaging Across the 7th Rank to Suffocate a Boxed-In Corner King)