agb2002: Black has a bishop and a knight for the bishop pair.White threatens fxe3.
Black can attack the white king and possibly the bishops with 28... Bxf2+ 29.Kxf2 (else drop a pawn) 29... Qc5+:
A) 30.Ke1 Qe3+ 31.Kd1 (31.Kf1 Ng4 and mate in two) 31... Qxc3, with an extra pawn and the threat Rb2, looks winning.
B) 30.Ke2 Ng4
B.1) 31.Kf3 Qf2+ (or 31... Qe3+ 32.Kg4 f5+ 33.Kh3(4) Qh6#) 32.Kxg4 (32.Ke4 Qe3#) 32... Qf5+ 33.Kh4 Qh5#.
B.2) 31.Rc1 Qe3+ 32.Kd1 (32.Kf1 Nxh2# or Qf2#) 32... Nf2+ 33.Kc2 Qd3#.
B.3) 31.Be1 Qe3+ 32.Kd1 Rb2 wins (33.Qa4 Nf2+ 34.Bxf2 Qd2#).
B.4) 31.Kd2 Qf2+ recovers the piece and keeps the attack.
B.5) 31.Kd3 Qe3+ 32.Kc2 Qe2+ looks similar to B.4.
B.6) 31.Qa7 Rb6, probably better than Qxc4+, and Black will resume the attack as sbove.
C) 30.Kf1 Qe3
C.1) 31.Qa7 Rb1+ 32.Rxb1 Qxa7 wins decisive material.
C.2) 31.Be1 Rb2 32.c5 Ng4 wins.
C.3) 31.Qa3 Ng4 and mate next.
D) 30.Kf3 e4+ 31.Ke2 (31.Kf4 Qf2+ and mate in three) 31... Ng4 looks similar to B except in the case of 32.Qa7 when 32... Rb6 loses to 33.Qa8+ and mate in two. However, Black has 32... Qxc4+
D.1) 33.Ke1 Qxc3+ looks winning.
D.2) 33.Kd2 Qd3+ 34.Kc(e)1 Qxc3+ looks winning.
D.3) 33.Kd1 Qd3+ 34.Bd2 Rb2 35.Qa5 Ne3+ 36.Ke1 (36.Kc1 Qc2#) 36... Nxg2+ wins.