What did black miss here?

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Streptomicin

One quiet game just go berserk after my bad move. Full annotations inside. 
PrawnEatsPrawn

25 .... Bxh2+

26 Kh1 Rxf2

Looks quite good for Black, the other knight is threatening mate on g3.

Streptomicin

LOL, 25...Bxh2+ 26.Kf1 Ng2#

PrawnEatsPrawn
[COMMENT DELETED]
PrawnEatsPrawn

ok, latest thoughts:

25 .... Bxh2+

26 Kh1 Rxf2

27 Rc3 Qe7

With dire threats on the dark squares, the White Knight cannot return to f3 because the White Rook needs to defend the g3 square.

Streptomicin
Streptomicin

27.fxg3 can not happen, pawn is pinned cuz of rook at f7.

PrawnEatsPrawn

For my money you haven't looked at the crital line yet (perhaps, I'm missing something):

25 .... Bxh2+

26 Kh1 Rxf2

EDIT:

Yes Kh1 a typo on my behalf

Streptomicin

So after 25.Bxh2+ 26.Kh1 is the only move.

PrawnEatsPrawn
Streptomicin wrote:

So after 25.Bxh2+ 26.Kh1 is the only move.


 Ok (Kh1 as I gave in my original post),  so what after 25.Bxh2+ 26.Kh1 Rxf2 .... looks like White is doomed.

Streptomicin

Ok, tnx, I was unaware that Ng4 opened line for Bishop too. 

But what about position after 29.th move.

PrawnEatsPrawn
Streptomicin wrote:

Ok, tnx, I was unaware that Ng4 opened line for Bishop too. 

But what about position after 29.th move.


 I think Black has blown it after 29 Nf4!. The threats along Black's back rank and the promoting pawn are mortal ones, also the Knight on f4 and the Queen on a7 cover all the vital squares in defence. I've looked at some of the sacrificial lines for Black but they all seem to come to nothing.

Streptomicin

Tnx.

2MoRRoW

27... Qxd6