Latvian Gambit: Diepstraten Countergambit is a chess opening with the ECO code C40, part of the Latvian Gambit family. It goes 1. e4 e5 2. Nf3 f5 3. c4. White opens with 1. e4 (the king's pawn) and Black answers 1... e5. After 5 moves it is Black to move. The lesson on the board explains every move of the line and lets you play it yourself; it is free.
The moves
1. e4 – White plays the pawn to e4
1... e5 – Black plays the pawn to e5
2. Nf3 – White plays the knight to f3
2... f5 – Black plays the pawn to f5
3. c4 – White plays the pawn to c4
About the Latvian Gambit
After 1.e4 e5 2.Nf3, Black plays the risky 2...f5. It is like a King's Gambit for Black, but a tempo down, so it is objectively dubious.
Black wants to open the f-file and attack fast.
White's strong reply is 3.Nxe5, hitting e5 and eyeing Qh5+.
The e8-h5 diagonal is weak for Black; watch for Qh5+ tricks.
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