What on earth is the Quaade Gambit, you ask? It's a line of the King's Gambit that begins 1.e4 e5 2.f4 exf4 3.Nf3 g5 4.Nc3!?, deviating from the usual Kieseritzky prescription of 4.h4 g4 5.Ne5. The line is named for a 19th-century Dutch sea captain (not to be confused with Captain Evans, a Welshman). The natural response is 4...g4 5.Ne5 Qh4+, when White responds with the surprising 6.g3! fxg3 7.Qxg4! Now Black can and should trade queens, when Black will be a pawn up but White's lead in development and better pawn structure give him sufficient compensation.
But who can resist the temptation to win a rook with 7...g2+ 8.Qxh4 gxh1=Q? Not many, according to the databases. But resist Black should, for after 9.Qh5! he is in big trouble. According to John Shaw in his magnum opus on the King's Gambit, Black's best chance is 9...Nh6! 10.d4 d6 11.Bxh6 dxe5 12.Qxe5+ Be6 13.Qxh8 Nd7 14.Bxf8 0-0-0 15.Qxh7 Nxf8 16.Qh6 Ng6 17.0-0-0 Rh8 18.Qd2 Qxh2 19.Qxh2 Rxh2 20.Bd3, when White is a pawn up in the endgame with good winning chances. In the game below, Black instead went down in flames, as he usually does in this line. White won a once-in-a-lifetime beauty of a game: