Haxo Gambit

The Haxo Gambit is a branch of the Scotch Gambit, 4. Bc4, in which Black answers with 4...Bc5 instead of entering the Two Knights Defense with 4...Nf6. The bishop goes to an active diagonal and protects the pawn on d4, so for the moment Black stays a pawn up. The cost is that the king's knight is still on g8, which leaves f7 short of defenders against the bishop on c4 and delays castling.

The most frequent reply, chosen in more than half of games, is 5. c3. White offers a second pawn and threatens to recapture on d4, building a broad c- and e-pawn center. Taking with 5...dxc3 is an error, because 6. Bxf7+ exploits both the weak f7-square and the unprotected bishop on c5; White wins back the material and keeps a dominant position. The normal answer, 5...Nf6, transposes to the Giuoco Piano, so in practice this move order is often simply a route into Italian Game theory.

The Sarratt Variation, 5. Ng5, adds a second attacker on f7. With the knight still on g8, Black cannot meet the threat by castling, and 5...Nh6 is almost always played. Exchanges of minor pieces usually follow, and White can also gain time by hitting the exposed bishop on c5.

With 5. O-O White puts development ahead of regaining the pawn, keeping c3 in reserve for later. If Black replies 5...Nf6, the game transposes to the Max Lange Attack, a line generally regarded as favorable to White. Black therefore tends to prefer 5...d6, which leads to irregular, double-edged positions where neither king is entirely safe.

The engine regards the starting position as roughly balanced, but White scores well in practice, and draws are rare. The position is reached often in online play, and most games quickly turn on concrete calculation around f7 and the d4-pawn rather than on slow maneuvering.