|Karpova: <A. Lewin> played this game as White in St. Petersburg:|
White to move:
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Black had prepared for the ♗ sacrifice on g6 and was sure to refute it with ...Qe5+ and ....Ng5+. However, the game went
1.Bxg6 Qe5+ 2.Kf3 Ng5+ 3.Qxg5 Qxg5 4.f7+ Kg7 5.f8=Q+ Kxg6 6.Qg8+ Kf5 7.Qxg5#
Source: 'Wiener Schachzeitung', July-August 1910, p. 249
Black was correct in assuming that the ♗ sacrifice was incorrect, however his refutation is refuted itself by the nice ♕ sacrifice. First of all, 1....e5+ is much stronger than the ♕ check (1...e5+ 2.Kf5 Qd3+). Secondly, with 2...Ng5+ Black gives away his advantage. Instead, Black seems winning after 2...Kh8 3.Be4 Ng5+ eliminating the possibility of a successful ♕ sacrifice (note that 3.Bxf7 is even worse for White after 3...Rd3+ and Black checkmates first).
Apart from that, the ♕ sacrifice is really beautiful!
(actually, the 6th move for Black is given as <K beliebig>, i. e. <K any>)