1.e4 c6 2.d4 d5 3.e5 Bf5 4.g4 This is by far the most aggressive approach to the Caro-Kann Advance, and has led to many a tactical slugfest. The idea is obviously to gain space and time over the bishop, as well as promote dangerous options if the pawns start rolling forward on the kingside. Though of questionable reputation, it is also a favorite of Shirov's.
4...Bd7 5.c4 e6 This line doesn't see much grandmaster play, and it is hardly surprising considering the awkward bishop on d7 and the unattractive development problems Black will need to solve.
6.Nc3 c5!!N Astonishing really, and if ever there was an opening novelty deserving of exclamation points, this is it. It isn't so much that Black is winning (he is not), but what it does to the evaluation of the position from both White's and Black's perspective. Instead of the old quiet behind the lines fight expected from Black while White tried to open lines and crack Black's position, now Black's pieces are about to take a very serious life of their own while White's g4 pawn looks like a very questionable weakness.
7.cxd5 [Though the engines don't condemn Shirov's choice, they do have a slight preference for 7.Nf3 Still, the question would remain: what the heck is that pawn doing on g4?]
7...exd5 8.dxc5 Bxc5
9.Bg2?! Shirov starts to go astray, but one cannot blame him for not wanting to take on d5 and potentially go down in flames. Unfortunately for him, that is exactly what happens. [9.Qxd5 Qb6 10.Bc4 Be6 (10...Bxf2+ is also possible, but leads to nothing decisive after 11.Ke2 Be6 12.Qb5+ Nc6 13.Bxe6 fxe6 14.Nf3 ) 11.Bb5+ Nc6 12.Bxc6+ bxc6 13.Qf3 protecting f2 and g4, though Black's chances are to be preferred due to the slightly better development and bishop pair.]
9...Ne7 10.h3 Qb6 11.Qe2 0-0 12.Nf3? A mistake that allows
12...d4! however the position was probably compromised as it was.
13.Ne4 Bb5 14.Qd2 Nbc6 Threatening Bb4.
15.a3 Ng6 16.b4 Be7 17.Bb2 Rfd8 0-1