An Extremely Nice Attack
The attacking idea in this game draws inspiration from the standard
Grand Prix Attack, where white is able to play Bb5 after
black’s Nc6. In this case, however, black prevents it with
his early 4... a6 move. I responded by correctly playing
5. g3 transposing into a closed Sicilian with a tempo up,
and carried out a similar attacking sequence
Qe1 g4 f5 Qh4 f5 Bh6 Ng5 and the sacrifice
Rxf6!.
Another nuance is that, normally white has a rook on a1 that can
swing across to f1 when Kxf6 happens. In this game, the
rook on a1 is also sacrificed, making the attack much more
calculation-intensive. Luckily, black did not find the only defending
move 20... Kxe5 (which is shocking!), and I was able to
score a nice win.