The strong Passed Pawn!

In this game, Alexander Alekhine advanced his Pawn with confidence into Charles Watson's territory. It acted as a catalyst for White's demise as Black's Queen, Rook, and Bishop follow through onto a nice post. (18... e4 was the beginning of the end 19. g3 e3 20. gxg4 exf2+ 21. Kxf2 Bxf4 and 27... Re3 would have made for a nice attack if White had not resigned!)