King's Gambit Declined: Falkbeer Countergambit

The King's Gambit Declined: Falkbeer Countergambit is a chess opening classified under ECO code C31 in the Open Games & French Defense family, beginning with 1.e4 e5 or 1.e4 e6, including the Italian Game, Ruy Lopez, and French Defense. It is reached after 2 moves: 1. e4 e5 2. f4 d5. The resulting position leaves white to move.