Italian Game:Two Knights Defense, Fried Liver Attack

Its old Italian name, Fegatello, means “fried liver”. White sacrifices a knight on f7 to drag Black’s king into the open.

It is reached after 11 moves: 1. e4 e5 2. Nf3 Nc6 3. Bc4 Nf6 4. Ng5 d5 5. exd5 Nxd5 6. Nxf7. It is a line of the Italian Game.

Black is to move and has 42 legal moves. Over the next four moves — two for each side — the game can branch into 2,275,140 different games. Those games reach 734,094 different positions: most positions can be reached in more than one way, 3.1 on average.

The Lichess opening list names 1 further line after this position, such as Fegatello Attack, Leonhardt Variation (6... Kxf7 7. Qf3+ Ke6 8. Nc3 Nb4 9. Qe4 c6 10. a3 Na6 11. d4 Nc7).

The same moves can be played in 726 different legal orders that all reach this position. For example 1. Nf3 e5 2. e4 Nc6 3. Bc4 Nf6 4. Ng5 d5 5. exd5 Nxd5 6. Nxf7, which starts as the Zukertort Opening.