Gilmoy: What is White doing? Is this book?
8 d5 closes the center, not to White's space advantage -- Black was going to break out on f regardless, White throws away his center counterplay.
12 g4 would have forked a Knight. White feared exposing holes around his King? But without this, White's 11 exf5 has only made Black stronger, by ceding f.
13 .. Bh6 14 Bc3?? Unbelievable -- White cedes the diagonal, and mothballs his own Bishop.
15 Re1? abandons f! Did White plan f4? Or Nf1-e3? White has momentary congestion approaching gridlock, no pressure on Black, no axis for counterplay.
Meanwhile, Black's development rolls smoothly: 16 .. Bf5 17 .. Qd7 clears back rank 19 .. Rf7 and the inevitable doubling on f. Now Rf1 just wastes two tempi, so White stays the course. 17 c5 18 cxd6 is a paper dragon -- White dreams of maybe tripling on d6 with Nc4 Bb4.
19 f3? Consistent with his "theme" of ceding f -- he'll "save" this pawn not by protecting it, but by having it sidestep.
20 Nc4 Bxe4 smoothly nips the threat to d6. 21 fxe4 and now Black sees that his Queen will soon sortie, but he needs his Rook unmolested at f7, hence he must chase the Knight: 21 .. b5 22 N(any -- a3, ok) The b-pawn needs no further protection, as White is out of time.
We arrive at the puzzle position. White has no defenders in the box around his King, a hole at h3, and Black (will) own f. Recall White's gridlock -- none of his pieces can (safely) protect g3. 22 .. Qh3? 23 Bf1 too hasty.
Examine the moves that smite! 22 .. Nxg3 and now 23 ... Qh3 is a deadly deep-fork: g3 and Ng4. 24 Qe2 Qxg3+ 25 Qg2 Qxd3 26 Rad1 looks dicey, but 26 .. Be3+ and:
27 Kh2 Bf5+ 28 .. Qg3
27 Kh1 Qxe4 28 Qxe4 Nxe4 and White has no time to take the Bishop: 29 Rxe3? Nf2+ and Black is up an exchange + 3 pawns.
So, 24 Qf3 Ng4 and White's King is trapped in a bowling alley, while his Queen fights alone vs. a 4-piece attack (not even counting Raf8). 25 Qg2 Qh5 (threatening 26 .. Rf2) 26 Qh1 Rf3 "zwickenfork" :) with check, as Black's Queen is protected.
29 Be2?? Rh3+ is a mating net featuring the gift square e3, e.g.
30 Kg1 Be3+ 31 Kf1 Rf8+ 32 Kg2 Rh2+ 33 Kg3 Bf4+ 34 Kf3 Rf2#
30 Kg2 Rh2+ transposing to the above.
<Aspirador: Better for white seems 26.Re2, but black still has an attack after 26...Raf8.>
26 Re2 cuts the Bishop from f1 -- more gridlock.
26 .. Raf8 27 Nxb5 Ne3 forks the Queen and mate at f1: 28 Q(h1,h2) Rf1+ 29 Rxf1 Rxf1#. Or 28 Rxe3 Bxe3+ winning.
Hence, White must defend e3 twice: 27 Rae1 a6! leaves White's Knight and KB with no prospects. Black's threat is a different fork 28 .. Nf2 29 Bc2 Nh3+ K(h1,h2) 30 Rf2 winning the Queen (either trapped or pinned). Can White answer that in 1 move (his 28th)?