Both sides are poised to break open the opposing king position. Which side will break first?
22. f5
This is a high-risk gambit. I expected h4 first, to hold the g5 pawn.
22... Qd8xg5
This too is a high risk pawn grab, as it gives White a half-open g-file straight to the Black king.
23. Kc1b1 Qg5f6
Threatening mate on b2.
24. c3
This loses yet a third pawn (a3) with check. The alternative, Qb3 holding b2 and a3, also loses a pawn (f5) but might have offered White some counterplay by putting his rooks on the half-open king-side files.
24... Nc4xa3 25. Kb1b2 a5 26. bxa5
Of course not KxN, for then . . . Rxc3+ winning the White queen. The White king is now perilously exposed; the tide is turning in Black's favour.
26... b4 27. Bg3e1
A serious error, as it loses control over the crucial b8 square and disconnects the White rooks. Better was Rc1, or f5xe6 in order to expose the Black queen to a rook threat on f1.
27... Na3c4 28. Kb2b3 bxc3 29. Be1xc3 Rf8b8
See note to move 27.: this encroachment of the rook via b8 is decisive.
30. Bc3b4
The final fatal error; mate follows in short order now. Relatively better was 30. Kc2 Nb2; 31. Qf3 NxRd1; 32. RxNd1 Rbc8 33. Rd3 d5d4 and the White bishop is lost.