After 1.e4 e5 2.f4 exf4 3.Nf3 d5, Black employs a counter-attacking strategy against the King's Gambit, aiming to challenge White's central control and develop pieces harmoniously. Key ideas include maintaining a solid pawn structure while preparing for active piece play, particularly through developing the dark-square bishop and creating counterplay against White's pawn on f4. This opening appeals to players who enjoy dynamic and tactical positions, allowing for both defensive resilience and opportunities for counterattack.