Gypsy: Duras is a player I go to when I am unhappy with my tactical vision. Here is a hundred-year old game from Duras first tournament as a "master with a diploma". He and Teichmann created enough combinative material here for about five normal, interesting games.
Move 14. Provocative 14.-Na5? would have lost a pawn.
Move 18. Today, such positions arise from KID. It would have been prefectly logical (and 'cleaner') for White to attack on the Q-wing with b3, a3, b4. However, K-side attacks suit Duras temperament better.
Move 22. Exchange Black bishop before f6 and Nf7.
Move 27. The threat was 28.e5 dxe5 29.Nh5 Qh8 30.Rxe5....
Moves 28-34. Game is in an interesting dynamic equilibrium: Black pieces occupy arguably better squares and lines, but their coordination is slower due to his space deficiency.
Move 35. If 35.-g4 36.hxg5 Bxg5, then 37.Qf4.
Move 38. Teichmann is allert. After 38.g4, White choice between 39.Rf4 and sharp 39.Nf5+ Bxf5 40.Rxf5 gxf5 41.Qg5+ is pleasant.
Move 41. Position after 41.-f5 42.Qf2 looks bad for Black.
Move 42. Only now we are geting to the fun part! Of course, White would love to sac 43.Nf5+ but black has that indirectly covered. So the next crazy option to consider is a speculative sac
43.Rf5! Would we dare? Duras did.
Move 43. Do we take the rook or do we counterattack? Damn if we do, damn if we do not. Unlike in the famous Keres-Smyslov, Zurich 1953 game, here Black could have skated to a draw if he did take the rook. Many famous annotators got it wrong, however (Foldelak, Mieses). The key is that after 43.Rf5 gxf5 44.Nxf5+ Kg6 45.Nxh6 Kxh6 46.Qe3+, two retreats of the king loose, but one seems to hold. This was discovered by a group of Prague masters back in fifties. They therefore speculated that Duras would have probably forced a draw after 46.Qh4+ Kg7 47.Rf3 f6! 48.Rg3+ Bg6 49.Qg4 Qg5 50.Qf3 Qe5 51.Qg4... All in all, we are just scratching the surface of possibilities of what could have happened here. For better or worse, Black declined the offer.
Move 44.e5! There are two benefits of this sac: One, it opens the lines of the White bishop; two, it closes the lines of the Black queeen.
Move 44.-dxe6. If 44.-Rxe5, mate follows in three moves.
Move 45.-Kh7. Immediate threats were Nf5+ and Qf6+.
Move 46.-gxf5. It is hopeless to surender quality here. Consolidation of the position would have been too easy for White.
Move 47.-Rg6. After 47.-Kh8 48.Rh5 Qe3 49.Kh2 Kg7 50.Qg4 White wins in interesting wariations.
Move 48.-Qd4+. Black uses this 'only' manuever to stave off Rh5+ and/or Qxe7.
Move 50.-e4. Black has to close the diagonal. After 50.-Rd7 simple 51.Rf3 wins.
Move 52.-Qe1! Once again, one and only move. The thereat was Rxf7. Intermezo 52.-Qxb3+ fails to 53.Rf3.
Move 53.Qxe8!! To a normal mortal it may still not be clear who will prevail in this fight. But, without a doubt, Duras already saw the end here. After taking the bishop, Duras was commited to sacrifice his queen. Enjoy the end.