thomastonk: The endgame after 41.. ♔g7 is quite interesting: 
click for larger view White took immediately on g7 (42.♗c5  ), and Black played the monster move 42.. ♗c3!! Not quite as spectacular as Topalov vs Shirov, 1998, but this move should win back the pawn at least, say 43.♗c5 ♗xb2 44.♔c2 , and the game is still about equal. But White thought, he will be able to stop the a-pawn after 43.bxc3 a3 44.♘e6 ♗a4 45.♘c5+: 
click for larger view Black is a piece down and another is en prise. Where shall the King go? Black went to c6, and after 46.♘d3! the game continues, because White can stop the a-pawn thanks to Black's bad king position. 45.. ♔c8! and 45.. ♔e8! were winning moves, while 45.. ♔e7?? runs into 46.♘b3!!  at least: 
click for larger viewThe endgame has a further interesting moment some moves later: 
click for larger view Black will win White's knight for the a-pawn, having a bishop for two pawns. In this moment, he has to make a decision on the pawn structure on the king side. The only winning move is surprisingly 51.. ♔e7!, though this allows 52.g6. This has taken me two hours, and my silicon friends were not of great help here. After all, the idea is simple: Black's king to h6, and Black's bishop to h5, and do this in such a way that White's king is on h3! Then ♗xg6 will result in a won pawn ending. Judd instead played 51.. fxg5+, which gives a drawn position. But 10 moves later, Ware made him a present with 61.♔f5?. Here it was possible to eliminate the last Black pawn by 61.♔d6 with the idea of ♔c5 and c4, of course. | 
Kibitzing
sac: 42...Bc3