Instead of Ng5, Nxd6 or Qxd6 were better moves. The Black queen wasn't posing any threat; ...h4 at any time would be answered by Bg4.

I see why Erika played it, though which was to gain tempo. And, I agree with Michael. However, of the 2 moves that he mentioned, 21.Nxd6+ was best. and it's more then just winning a pawn. As is shown in the diagram, black would also be in check, and thereby, lose his right to castle.

In my view, best was 21.Bg2, after which 21...Qe6 would have been forced (can you see why?). Then White could have played 22.Nxd6ch, followed by 23.Nxb7. Now White seems to have nothing better than 22.Ne4.

22.Be4?? lost a piece. Your best move was 22.Ne4 which would threaten 23.Nxd6+

?? I see the point of this, but it's going to cost you another pawn, and black's about to have a forced since it will also give him an unstoppable passed pawn, as you're about to see.

Oops...

What? Now your kingside is dead. That being said, black’s king is also exposed. 23. Qxd6 was probably best.

Better seems 24.Bg2, with prospects still of attack.

This is what I'm talking. No matter what you do, white is now lost, Erika. All that's needed now is advancing the h pawn and using the Queen since the Rook is behind the pawn which gives black an overwhelming attack. As now, he has too much of an army against the King.

I can see why Joe is so apprehensive, but with correct play, White is actually winning here! What to play? Not 25.Rg1?? Qh3#, end of game. No good either is 25.Qxd6, on account of 25...Qh3ch 26.Kg1 Qe3ch 27.Kh2 Qxe4, as White simply has insufficient attack for the lost piece. Best is 25.Rf3! ... with the idea 25...Qg4 26.Qxd6 Ne7 (to protect the twice-attacked g-pawn) 27.Qxe5 Rh5 28.Qg7 ... with 29.Rg1 Qe6 30.Re1 ... to come.

A losing move. But the game was very complicated hereabouts, and has been for a while. Missing chances is not to be wondered at. It is part of the development of a player's tactical vision to involve oneself in complicated, tactical positions such as appeared in this game. White had but one good move in this position - 25.Rf3 - but that move could (and should) have been the winning of the game.

Yes, Rf3 and Qf3 are the only solutions I see

I know why he did this, but best was 25...Qxg6 winning the B. Yet, black still has a win.

Best try, in the circumstances. White is in real trouble, but there is at least some chance of fighting one's way out of it.

Having said that, best was 26...h3, and from there it's mate with 27...Qg2#

Joe's suggestion, 26...h3, looks good, but only for a level game. The right move here was to bring in the knight: 26...Nd4!. After this wholly irrelevant pawn move, White is back in the fight.

Again: quite irrelevant. The action is happening on quite the other side of the board, and in the centre. 27.Rf3 (that move again) was the right way to go: 27.Rf3 Qg5 28.f6ch Kd7 and now, for some tactics: 29.Qd5!! Qxg6 30.Rg1 Qe8 31.Rg7ch Kc8 32.f7 ... (NOT 32.Qxd6 Qd8! and White's attack peters out, still a knight down) 32...Qf8 33.Rg8 Kc7!! (NOT 33...Rxg8 34.fxg8=Q White wins) 34.Rxf8 Rfxf8 with an even fight in the end game. Black would have Rook, knight and two pawns for the queen, but a rather passive position.

27...h3 was still called for, and for the same reason.

27...h3 is no better than the text. The right move would have been 27...Qh3ch 28.Kg1 Nd4, with winning attacking prospects.

There is certainly a theme running through White's counter-attack right now! But maybe 28.Qd5 would have been a slight improvement, inviting Black to take the draw by repetition: 28...Qh3ch 29.Kg1 Qg3ch 30.Kh1 ... etc.

28...Kd7! was safe. This retreat give White a great chance to finish the game off quickly.

Wrong move order, though it is part of the plan. White could wrap up the game by 29.Qxd6ch! Kg8 30.f7ch Kg7 (NOT 30...Kh8 31.Qf6#) 31.f8=Qch Rxf8 32.Qxf8ch Kxg6 and now White can win the queen for rook by 33.Rg1 ... (pinning the Q) or play for mate by 33.Qf7ch Kg5 34.Qf5#.

Yikes! Black had a forced win: 29... Qh3+ 30. Kg1 Rxg6+ 31. Kf2 Rg2+ 32. Ke1 Qe3+ 33. Qe2 Qxe2#.

?? That's true, but black had a forced win earlier. The solution wasn't 29...Qh3+ but 29...h3 which wins a move later, as noted on black's 26th move since the opportunity was there from that point. This, however, is now the turning point in the game since white now has a forced win, as Michael notes below.

Both sides are yielding up to their opponents forced wins!

And now it's White who has a forced mate.

Bingo! All White has to do is find the next move...

31. f8Q+ Rxf8 32. Qxf8+ Kxg6 33. Qg8+ Kh5 34. Rf5+ Qg5 35. Rxg5#. Note that the finish is almost identical to Black's missed mate, rotated 90 degrees!

Yes, Queening would've led to mate, but it would also be easy to overlook something. You'd have to continue with the checks to deliver mate and prevent black from mating. In other words, if anyone makes a mistake, they'll be lost. Having said that, black can win again now.

A quicker mate, which we have seen before: 31.f8=Qch Rxf8 32.Qxf8ch Kxg6 33.Qf7ch Kg5 34.Qf5#.

Leaves the previous mate still on. Instead, 31... Qh3+ 32. Kg1 Qg3+ is a draw, and 32... Rxg6+ 33. Qxg6 Kxg6 34. f8Q Rxf8 35. Rxf8 reduces things to an endgame that Black should win.

Michael is correct, but the issue is timing. Had black played this several moves earlier, there'd be nothing that white could do to stop mate.