Four Knights Game

In the Four Knights Game, 1.e4 e5 2.Nf3 Nc6 3.Nc3 Nf6, both sides develop their knights first and keep every pawn break in reserve. White chooses the character of the game on move four: 4.d4 for the Scotch Four Knights, 4.Bb5 for the Spanish, 4.Bc4 for the Italian version that allows the fork trick, or 4.g3 for the quiet Glek System.

The most frequent mistake in our data is the bishop sacrifice on f7. After 1.e4 e5 2.Nf3 Nf6 3.Nc3 Nc6 4.Bc4 Bc5 5.d4 exd4, White plays 6.Bxf7+? and after 6...Kxf7 the follow-up checks lead nowhere. White has simply given up a bishop.

The second theme is the e5 pawn. In the Glek System, after 4.g3 Bb4 5.Nd5 Bc5, the capture 6.Nxe5? loses a knight to 6...Nxe5, because the pawn was defended and there is no fork to follow. The same happens after 1.Nc3 e5 2.e4 Nc6 3.Nf3 Nf6 4.d3 Be7 5.Nxe5? Nxe5. In the Spanish Four Knights, after 4.Bb5 Bc5 5.Bxc6 bxc6 6.Nxe5, Black's attempt to win the pawn back with 6...Nxe4? fails to 7.Nxe4.

The fork trick itself, ...Nxe4 followed by ...d5, only works with the bishop on c4 and nothing else going on. After 4.a4 g6 5.Bc4, the extra moves change everything, and 5...Nxe4? 6.Nxe4 leaves Black in serious trouble.

The lesson is the same in every line: before taking a pawn or sacrificing on f7, count what defends it and what comes next. The Four Knights Game study explains the main lines, the fork trick and the Halloween Gambit; the puzzles below come from these real positions.