Evans gambit (Chess)

The Evans Gambit is a chess opening characterised by the moves: 1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. b4 The Evans Gambit is an attacking line of the Giuoco Piano. White offers a pawn to divert the black bishop on c5. If Black accepts, White can follow up with c3 and d4, ripping open the centre, while also opening diagonals to play Ba3 or Qb3 at some point, preventing Black from castling kingside and threatening the f7-pawn, respectively. If Black declines, the b4-pawn stakes out space on the queenside, and White can follow up with a4 later in the game, potentially gaining a tempo by threatening to trap Black's dark-square bishop. According to Reuben Fine, the Evans Gambit poses a challenge for Black since the usual defences (playing ...d6 and/or returning the gambit pawn) are more difficult to achieve than with other gambits. (Fine was once beaten by this gambit in a friendly game against Bobby Fischer, in just 17 moves.) The Encyclopaedia of Chess Openings has two codes for the Evans Gambit, C51 and C52.