411 REFERENCE · Wikibooks
Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Nc3/3...Nf6/4. Bc4
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Italian variation C47 Four knights game → 4. Bc4!?
Two knights defence → 4. Nc3!?
4. Bc4!? · Italian variation
White combines the typical Italian game bishop placement, Bc4, with the four knights game. This position arises most commonly in amateur games, from either the four knights or Italian games.
White seems to have made reasonable developing moves and is ready to castle. Their bishop on c4 targets f7 and White is ready to castle. However, Black has a tactical trick (4...Nxe4!) which has made masters shun away from this position.
4...Nxe4! is the strongest move. The apparent knight sacrifice is only temporary. After 5. Nxe4, Black plays 5...d5!, forking White's knight and bishop. This is known as the "centre fork trick" and occurs in several lines where White has a bishop on c4 or Black has one on c5. The best continuation is 6. Bd3 dxe4 7. Bxe4: White regains the lost material, but is at a space disadvantage. Black has equalised: "a good Fork Trick has the same approximate value as getting the White pieces."
If Black wants to accept a normal game, there is nothing particularly wrong with a natural developing move like 4...Bc5, but 4...Nxe4! is the best move in the position, and White is then fighting for equality.
History
Tarrasch played this against Lasker in the 1916 World Championship, and was crushed.Tarrasch v Lasker, 1916. Chessgames.com
Below the master level, this position crops up very often. In the Lichess amateur database, 4. Bc4 is the most common move in the four knights, played in one in three games.Opening · Four Knights Game, Lichess.org Larry D. Evans says that his students wind up in this line about once a tournament.The Fork Trick Evans Larry D. https://uscf1-nyc1.aodhosting.com/CL-AND-CR-ALL/CL-ALL/2000/2000_04.pdf Chess Life 32-33 April 2000
Since 4. Bc4 is played so often, learning the theory on 4...Nxe4 will let you get many good positions with Black after only a few moves.
Theory table
1. e4 e5 2. Nf3 Nc6 3. Nc3 Nf6 4.Bc4
4
5
6
Bc4Nxe4
Bxf7+Kxf7
Nxe4d5
-/+
...Nxe4
Nxe4d5
Bd3dxe4
=
...Bc5
=
References
See also
Four Knights Game