Alekhine's gun is a formation in chess named after the former world chess champion Alexander Alekhine. It is a specific kind of battery. This formation was named after a game he played against Aron Nimzowitsch in Sanremo 1930, ending with Alekhine's decisive victory.

Concept
The idea consists of placing the two rooks stacked one behind another and the queen at the rear. This can lead to substantial material loss for the opponent as it places considerable pressure on the "target" of the gun, especially if it is pinned (in this case it was only four moves before ).

Original "Alekhine's gun" game
Here is the game that spawned Alekhine's gun:

Other games
Six years later, in 1936, Alekhine defeated William Winter using Alekhine's gun again.  Since then, players have learned much about using and guarding against this formation; however, some international games are still lost or won by the force of this tactic. In November 2018 it was successfully used by Ju Wenjun against Kateryna Lagno in game 4 of the FIDE Women's World Championship. The attack could have been refuted with perfect defense, but Lagno was unable to find it and resigned five moves later. Ju Wenjun went on to win the match and with it the title.

In popular culture
The video game Alekhine's Gun is named after this chess formation.

References

Chess tactics
Chess terminology