Greek gift sacrifice

In chess, the Greek gift sacrifice (or classical bishop sacrifice) is a typical sacrifice of a bishop by White playing Bxh7+ or Black playing Bxh2+.

Greek gift sacrifices, or the threat of them, occur relatively frequently in play, especially at the lower levels. One of the most famous examples of the sacrifice is found in the game Edgard Colle versus John O'Hanlon, Nice 1930. Less commonly, a Greek gift sacrifice may be the prelude to a double bishop sacrifice, as seen in the game Lasker versus Bauer, Amsterdam 1889.

The position after the moves 1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.e5 Nfd7 5.Nf3 Bb4 6.Bd3 0-0?? (see diagram) is a simple case where the Greek gift sacrifice works. White can play 7.Bxh7+! Kxh7 8.Ng5+ to force Black to give up the queen to prevent mate:

Black could play 7...Kh8 instead, but due to poor king safety, it also leads to a lost position:

These variations are typical of many Greek gift sacrifices, though the outcome is not always so clear-cut.

The etymology of the phrase "Greek gift" in this context is not entirely clear. The obvious explanation is that it alludes to the Trojan Horse, and specifically to Laocoon's famous "timeo danaos et dona ferentes" ("I fear the Greeks even [when they are] bringing gifts", Virgil's Aeneid II.49). The Oxford Companion to Chess, however, suggests that one explanation is that the sacrifice often occurred in Gioachino Greco's games.

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