The crucial error seems to be 14...Bf6 - superficially a good move, defending e7 and making space for the king on g7 (and of course the Nc6 can't be taken - 14...bxc6? 15.Bxc6 Rb8 16.Rd8+ Bf8 17.Bh6 is murderous, and 15...Bh3 16.Bxa8 isn't much better).

Yet 14...Bf6 loses in the game after 15.Rd8+ Kg7 16.Nxe7! - a beautiful combination.

Instead, 14...Bg4!? gives Black some activity at the cost of another pawn or two. Even then, though, 15.Nxe7+ Kf8 16.Rb1! gives White a great many threats and a definite edge.

Another option is 14...Bf8, but it's very passive.

Stockfish 12 is calling it close to a draw:

13. Nxc6

(13.
Nxc6 (♘d4xc6 ♖d8xd1 ♖a1xd1 ♗g7-f8 ♖d1-b1 h7-h5 ♖f1-c1 ♕c3-f6 ♘c6-b4 h5-h4 ♘b4-d5 ♕f6-e5 ♘d5-f4 ♕e5-c7 g3xh4 e7-e6 ♖b1-b5 ♖a8-b8 c5-c6 b7-b6 ♖b5-g5 ♗f8-e7 ♖g5-g4 ♔g8-h7 ♗g2-e4 ♗e7-d6 h4-h5 f7-f5 h5xg6+ ♔h7-g8 ♘f4-d5 ♗d6xh2+ ♔g1-h1 e6xd5 ♗e4xd5+ ♔g8-g7 ♖g4-h4 ♕c7-d8 ♖h4-h7+ ♔g7xg6 ♖h7-h6+ ♔g6-g7 ♔h1xh2 ♕d8xd5 ♖c1-g1+ ♔g7-f7 ♖h6-h7+ ♔f7-e8 ♗e3-f4) +0.54/39 190)

CG puzzles aren't always to find a win. They're to find the best move.

I was struggling with this one to start with until I stopped looking for a win and started looking for mere survival for white. White does, after all, seem to be in dire straits.

Other candidates like <13.Rc1> can be quickly dismissed (13.Rc1 loses to 13...Rxd4). At least I can't find one that comes even close to working. That leaves <13.Nxc6> as the only possible solution since it minimises material loss and actually gives white a bit of initiative.

The rook on d8 and Black's back rank become defenseless after 13.Nxc6.

However, the position is unclear after 13... Rxd1 14.Raxd1 Bf8 (14... bxc6 15.Rd8+ Bf8 16.Bh6 Qg7 17.Bxg7 wins decisive material) because, if 15.Rd8, Black has 15... bxc6 16.Bh6 Bb7.

White can win the b-pawn with 15.Nd8 (instead of 15.Rd8) but I'm not sure whether this gives enough compensation.

It's better to play Bxc6 and Rd8+ in the other order netting a whole piece (see my previous post).

In that case, this is a rather obvious puzzle for a Thursday. The move is pretty much forced.

These white (black) to move and avoid losing are fairly rare but have come around once every few months, or so it feels to me. Likewise the red herrings where it looks like there's a forced win but it's a trap, although in that case I can't remember seeing one of those for simply ages.

from the "About Our Puzzles" link (just under the board position on the home page):

"What kind of move am I looking for?

"The goal is to find the best move, or sequence of moves, in the given position.

"You do not always have to find a checkmate! Just find the best move.

"Usually, this move will lead to a superior position, either by a forced sequence of moves which leads to checkmate, or (more commonly) wins substantial material.

"By "substantial material" we mean usually winning at least the exchange (i.e. trading a knight or a bishop for a rook). More commonly the winning move will net a whole piece (bishop/knight/rook) and sometimes will win the queen. Occasionally, the material will be only a single pawn--this usually happens in endgame situations where the extra pawn will surely decide the game.

"The first move is not always the most difficult move to see. Sometimes, the initial move in the sequence is somewhat obvious, but the real solution to the position lies in the follow-up moves. In order to solve our puzzles, you must see enough moves to demonstrate that the initial move is correct. Simply guessing the first move, without understanding why it works, is not solving the puzzle.

"Sometimes we will present a position where the player who is to move is in a nearly hopeless situation. In these positions you are expected to look for a way to draw the game instead of win it. We don't tell you that you are looking for a draw; you are expected to figure this out by the nature of the position."