Defenders must be warned, however, as they were in the American Supplement to Cook's 'Synopsis' (1885) that it is "not an attack to be trifled with".
Both players in the game below threw fortune to the wind. Each will no doubt learn from their insights and oversights.
rigidwithfear - deriver69
Giuoco Piano Jerome Gambit Tournament
RedHotPawn, 2016
1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+
4...Kxf7 5.d4 Nxd4
Black's two alternatives for capture, 5...exd4 and 5...Bxd4, are stronger. Leaving the pawn at e5 open for capture gives Whites' ideas - and chances.
6.Nxe5+
6...Ke6
Feisty - and foolish. The equivalent to drawing to an inside straight.
Instead, 6...Kf8 is the safest and leaves Black with the advantage.
7.f4
White does not realize his good luck. Instead, he had 7.Qg4+!? which promises good things: 7...Kxe5 (Forced; 7...Kf6 leads relentlessly to checkmate: 8.Qf4+ Nf5 9.Qxf5+ Ke7 10.Qf7+ Kd6 11.Nc3 Bxf2+ 12.Ke2 c6 13.Nc4+ Kc5 14.Kd3 Qa5 15.Qxf2+ Kb4 16.a3+ Qxa3 17.bxa3#; there is little hope in 7...Ke7 8.Qxg7+ Kd6 9.Nf7+ Kc6 10.Nxd8+ or 7... Kd6 8.Nf7+ Ke7 9.Nxd8 Nxc2+ 10.Kd1 Bd4 11.Kxc2 d6 12.Qg3 Kxd8) 8.Bf4+ Kf6 (8...Kxe4 9.Nc3 checkmate, Darrenshome - WildErmine, blitz, FICS, 2006 [1-0, 9]) 9.Bg5+ Kf7 7.Bxd8 and the Black Queen is gone, anyway.
7...d6
Black is not familiar with this gambit, and so he defends. His best chance was to counterattack with 7...Qh4+ 8.g3 Qh3 and he would be better.
8.Qg4+ Ke7
Avoiding 8...Kf6 9.Qg5+ Ke6 10.f5+ Kxe5 11.Bf4+ Kxe4 12.Nc3 checkmate, similar to Darrenshome - WildErmine, blitz, FICS, 2006, mentioned above.
9. Qg5+
Ouch. He had 9.Qxg7+ Ke6 10.Qf7 checkmate
9...Ke8
The "only" move, but a saving one. Now the odds turn against the Gambler again.
10.Qxg7 dxe5 11.Qxh8 Nxc2+ 12.Ke2 Bg4+ 13.Kf1 Qd1 checkmate