chess Chess is a board game for two players. It is an abstract strategy game that involves Perfect information, no hidden information and no elements of game of chance, chance. It is played on a square chessboard, board consisting of 64 squares arran ...

, a windmill (or seesaw) is a

tactic Tactic(s) or Tactical may refer to: * Tactic (method), a conceptual action implemented as one or more specific tasks ** Military tactics, the disposition and maneuver of units on a particular sea or battlefield ** Chess tactics ** Political tacti ...

in which a piece repeatedly gains while simultaneously creating an inescapable series of alternating direct and discovered checks. Because the opponent must attend to check every move, they are unable to prevent their pieces from being captured; thus, windmills, while very rare, tend to be extremely powerful. A windmill most commonly consists of a rook supported by a

bishop A bishop is an ordained member of the clergy who is entrusted with a position of Episcopal polity, authority and oversight in a religious institution. In Christianity, bishops are normally responsible for the governance and administration of di ...

. The bishop typically sits on the long diagonal (see

Fianchetto In chess, the fianchetto ( or spelling pronunciation ; "little flank") is a pattern of wherein a bishop is developed to the second of the adjacent b- or g-, the having been moved one or two squares forward. The fianchetto is a staple of man ...

), while the rook moves to the seventh (White) or second (Black) rank and checks the king, who is forced to the corner due to a friendly piece (usually a knight, but it can also be another rook) blocking it. Moving the rook leads to a discovered check by the bishop, giving the player a tempo by forcing their opponent to move the king. The rook then moves back to its original spot, and the process repeats until no more pieces can be captured. Windmills can also be done with other pieces, as seen in the Game of the Century.

Examples

Torre vs. Lasker

In the position diagrammed, from the game Carlos Torre–

Emanuel Lasker Emanuel Lasker (; December 24, 1868 – January 11, 1941) was a German chess player, mathematician, and philosopher. He was the second World Chess Champion, holding the title for 27 years, from 1894 to 1921, the longest reign of any officially ...

, Moscow 1925, White sacrifices his

queen Queen most commonly refers to: * Queen regnant, a female monarch of a kingdom * Queen consort, the wife of a reigning king * Queen (band), a British rock band Queen or QUEEN may also refer to: Monarchy * Queen dowager, the widow of a king * Q ...

in order to set up the windmill: : 25. Bf6 Black must accept the sacrifice, as his own queen is unprotected, 25...g5 26.Qxh6 leads to unstoppable mate on g7 or h8, and any other attempt to stop the windmill would simply give White the queen. : 25... Qxh5 26. Rxg7+ Kh8 27. Rxf7+ White gives discovered check by the bishop. : 27... Kg8 28. Rg7+ Kh8 29. Rxb7+ White simply repeats the checking cycle, capturing as many pieces as he can with his rook. : 29... Kg8 30. Rg7+ Kh8 31. Rg5+ Kh7 32. Rxh5 White concludes the windmill by taking the black queen. Black forked White's rook and bishop with 32... Kg6, but White still emerged three pawns ahead after 33.Rh3 Kxf6 34.Rxh6+ and went on to win.

Byrne vs. Fischer

The Game of the Century featured a windmill involving a

knight A knight is a person granted an honorary title of a knighthood by a head of state (including the pope) or representative for service to the monarch, the church, or the country, especially in a military capacity. The concept of a knighthood ...

and a bishop. The game continued from the diagrammed position as follows: : 17... Be6!! Black sacrifices his queen in order to initiate an attack. : 18. Bxb6 Accepting the sacrifice allows Black to set up the windmill. : 18... Bxc4+ 19. Kg1 Ne2+ 20. Kf1 Nxd4+ 21. Kg1 Ne2+ 22. Kf1 Nc3+ 23. Kg1 axb6 Black emerges with an overwhelming advantage.

References

{{chess Chess tactics Chess terminology