Black plays the startling 18... Rxc3 which looks like it will win a rook and two pawn for two pieces, except White backed down and gave up a pawn.

Then Black built up towards getting a c-pawn passer.

Then 32 ... Nxg3 looks like a foolhardy piece sacrifice for Black in an overwhelming position. Maybe a miscalculation?

After this, complications ensue. Maybe White could have broken through on the kingside.

White didn't find a way to stop the passser without the extra piece.

Then just as it looked like Black would win but White had the saving resource Ne6! attacking white king on the way to stopping the pawn.