I wasn't certain how White's knight and bishop wound up in a pawn fork, but I felt pretty certain that moving the knight was key to the position. Also, it was pretty clear to me that given the position of White's queen on the board, that White intended a king side mating type of attack. Therefore, material loss such as the bishop would be acceptable.

Given the above, I looked at three options for move 26. Nxe7+, Nh6+ and Nxg7. 26. Nxe7+ Qxe7 brought me nothing.

26. Nh6+ gxh6 (Kh8? 27. Nxf7+ Kg8) 27. gxh6 (Qxh6 was a dead end since the h7 pawn was protected by Black's knight and king) followed by Rg1 seemed promising but I could not prevent Ng6 and again, my attack was dead in the water.

26. Nxg7 was all I had left. Initially, I thought Black's response would be Kxg7 because after 27. Qh6, White has mate in two. But, then I saw 26. Nxg7 Kxg7 27. Bd4+ Kg8 28. Qh6 e5 29. Bxc5 and Black's position starts to deteriorate rapidly. Although, given how things did work out, Black should have taken the knight.

20.B:g7 Bd8

(20...Nce6 21.Nh6+ K:g7 22.Q:f7+ Kh8 23.Qg8# )

21.B:f8 K:f8 22.Qh6+ Ke8 23.Nd6+ Kd7 24.N:b7 N:b7 25.R:d5+ winning

In order to accomplish that objective (i.e. using difficult puzzles to teach notices), the puzzles should be broken down into parts. Then those parts need to be organized from the simplest to the most complex. The simpler parts should be taught first, followed by progressively more complex parts until the novice can follow the entire combination.

Here's a group of puzzle parts broken down from the end of today's Saturday puzzle (19. ?), which could be used to teach a mate-in-five.

1. Mate-in-two:

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2. Mate-in-three

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3. Mate-in-four

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4. Mate-in-five

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After 16...b4 White has three hanging pieces, and ignores all three.

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Stockfish_19092522_x64_modern:

19. Nxg7

(19. Nxg7
(♘f5xg7 ♔g8xg7 ♗e3-d4+ ♔g7-g8 ♕h5-h6 e6-e5 g5-g6 ♗e7-g5+ ♕h6xg5 ♘f8xg6 ♗d4xc5 ♕c7-d7 ♕g5-h6 ♖c8xc5 ♕h6xh7+ ♔g8-f8 ♖d1-g1 ♗b7xd5 ♖g1xg6 ♕d7xh3 ♕h7xh3 f7xg6 ♘c3xd5 ♖c5xd5 e4xd5 ♖a8-d8 ♕h3-h8+ ♔f8-e7 ♕h8-g7+ ♔e7-e8 ♕g7xg6+ ♔e8-e7 ♕g6-h7+ ♔e7-f8 ♕h7-a7 ♔f8-g8 ♕a7xa6 b5-b4 ♕a6-b6 ♖d8-f8 ♕b6xd6 ♖f8xf2 ♕d6-e6+ ♔g8-f8 ♕e6xe5 ♖f2-g2 ♕e5-d4 ♖g2-g6 ♕d4xb4+ ♔f8-g7 ♕b4-d4+ ♔g7-f7 c2-c4 ♖g6-f6 c4-c5 ♔f7-g7) +11.64/37 414)

This suggests 19.Bd4, making the most of this main diagonal:

A) 19... exd5

A.1) 20.Bxg7 Bd8 (20... g6 21.Nh6#; 20... dxe4 -or 20... f6- 21.Nh6+ Kxg7 22.Qxf7+ Kh8 23.Qg8#) 21.Qh6 Nce6 22.Bxf8 wins (22... Nxf8 23.Qg7#).

A.2) 20.Qh6 Nce6 (20... gxh6 21.Nxh6#) 21.Rg1 (due to 21... Bxg5+) and Black has problems to stop Bxg7. However, 20.Bxg7 looks easier to me.

B) 19... Ng6 (trying to escape to the queenside) 20.Qxh7+ Kf8 21.Qh8+ Nxh8 22.Rxh8#.

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Stockfish_19092522_x64_modern:

19 Nxg7 is the only clearly winning move; Bd4 leaves white with an advantage but not yet won:

1) +5.75 (20 ply) 19.Nxg7 Bxd5 20.Qh6 f5 21.Nh5 Kf7 22.exd5 b4 23.Bxc5 Qxc5 24.Nf6 e5 25.Qh5+ Kg7 26.Nd7 bxc3 27.Nxc5 cxb2+ 28.Kxb2 Rxc5 29.f4 Rb8+ 30.Ka1 Rxc2 31.fxe5 Rg2 32.e6 Bxg5 33.Qf7+ Kh8 34.Qxf5

2) +1.29 (19 ply) 19.Bd4 Bxd5 20.Qh6 Bxg5+ 21.Qxg5 f6 22.Qxg7+ Qxg7 23.Nxg7 Bxe4 24.Nh5 Bg6 25.Nxf6+ Kf7 26.Rf3 Ke7 27.Re1 Rc6 28.Ncd5+ Kd8 29.Ng8 Ncd7 30.Bb6+ Ke8 31.Nc7+ Rxc7 32.Bxc7 Rc8 33.Ba5 Rxc2+ 34.Kb1

Should black have played 13 exf5? Stockfish says no, black played the best move.

Here we have:

1) +0.17 (23 ply) 13...b5 14.Nxe7+ Nxe7 15.f3 Bb7 16.h4 d5 17.Bxc5 Qxc5 18.exd5 Nxd5 19.Nxd5 Bxd5 20.Bxd5 exd5 21.Kb1 Rac8 22.Rge1 a5 23.h5 h6 24.Qd3 b4 25.Qf5 Rfd8 26.Re5 a4

After exf5:

1) +1.20 (24 ply) 14.gxf5 Nxb3+ 15.axb3 Kh8 16.Qh5 Rg8 17.Nd5 Qd8 18.Qxf7 Bd7 19.Nxe7 Qxe7 20.Qxe7 Nxe7 21.Rxd6 Bc8 22.Bd4 Bxf5 23.exf5 Nxf5 24.Rd7 Nxd4 25.Rxd4 Rad8 26.Rgd1 Rde8 27.f3 Re2 28.Rd7 Rxh2 29.Rxb7 Rc8

But this didn't hold the next move. After 14 Bd5, he should have taken the bishop; but the actual Bb7 wasn't much worse:

1) -0.39 (20 ply) 14...exd5 15.Nxd5 Qb7 16.f3 Kh8 17.Qd2 Bxf5 18.gxf5 Rg8 19.Nxe7 Nxe7 20.Qxd6 Nxe4 21.fxe4 Qxe4 22.Bc5 Nxf5 23.Qd5 Qxd5 24.Rxd5 Nh4 25.a4 f6 26.Rg3 bxa4 27.Ra3 Rgc8 28.Bd4 Kg8 29.Rxa4

2) +0.01 (20 ply) 14...Bb7 15.Bxc6 Bxc6 16.Nd5 Bxd5 17.Nxe7+ Qxe7 18.exd5 Rac8 19.h4 Na4 20.dxe6 fxe6 21.Kb1 Rc4 22.Ka1 d5 23.Bd4 a5 24.h5 Rfc8 25.c3 b4 26.cxb4 Rc2

Black could take the lead with 15 b4!

1) -1.16 (21 ply) 15...b4 16.Bxc6 Bxc6 17.Bxc5 dxc5 18.Nxe7+ Qxe7 19.Nb1 c4 20.Qe3 Ba4 21.Rd4 Rfc8 22.c3 e5 23.Rd5 Rab8 24.h4 Qb7 25.cxb4 c3 26.Nxc3 Qxb4 27.Rd2

After Rfc8 though, this crazy game is pretty even:

1) +0.22 (21 ply) 16.Bxc6 Bxc6 17.Nd5 Bxd5 18.Nxe7+ Qxe7 19.exd5 Rc7 20.Kb1 Rac8 21.dxe6 Nxe6 22.Rd2 Rc4 23.Qd3 R8c6 24.f3 Qc7 25.Rgd1 b4 26.Rf2 Qa5 27.b3 Rh4 28.Qd5 Qxd5 29.Rxd5

On 16, once again the computer wants b4! giving black a lead, but Ne5 gives white a .46 advantage:

1) -1.07 (19 ply) 16...b4 17.Bxc6 Bxc6 18.Nxe7+ Qxe7 19.Bxc5 dxc5 20.Nb1 c4 21.c3 Ba4 22.Rd4 Qc5 23.Qe3 a5 24.f4 Qb5 25.Qf2 Rab8 26.h4 Rd8 27.Nd2 Rxd4 28.cxd4 Rd8

1) +0.46 (23 ply) 17.Bxb7 Qxb7 18.Nxe7+ Qxe7 19.f4 Ng6 20.a3 Qb7 21.Bxc5 dxc5 22.f5 Nf8 23.f6 b4 24.Nb1 Ng6 25.fxg7 Kxg7 26.Qf3 Kg8 27.Rh3 Rd8 28.Rxd8+ Rxd8 29.Nd2 Qe7

So we finally get to the losing move, 17 Ng6?

1) +5.66 (20 ply) 18.Qh5 Nf8 19.Nxg7 Bxd5 20.Qh6 f5 21.Nh5 Bd8 22.Bxc5 dxc5 23.exd5 b4 24.Na4 e5 25.Nf6+ Bxf6 26.gxf6 Ng6 27.d6 Qf7 28.d7 Rd8 29.Nxc5 Ra7 30.Rd6 Kh8 31.Rg3 Kg8 32.Rg1

Black should take the knight:

1) -0.87 (23 ply) 17...exf5 18.exf5 Qd7 19.f4 Qxf5 20.Bxc5 Rxc5 21.Bxb7 Ra7 22.Qg2 Qxf4+ 23.Kb1 Nc4 24.Nd5 Qe5 25.Nxe7+ Qxe7 26.Qe4 Qxe4 27.Bxe4 g6 28.b3 Re7 29.Rh4 Ne3 30.Rd3 d5 31.Rxe3 Rxe4 32.Rexe4 dxe4 33.Rxe4 Rxg5

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Stockfish_19092522_x64_modern: