Puzzle of the week #197

Chess Diagram: 

[Event "Puzzle #197"][Date "2012.05.14"][Result "0-1"][SetUp "1"][FEN "4rrk1/1pp2qpp/p2b4/3p4/6b1/2P1B3/PP1Q1PPP/R3KN1R b KQ - 0 1"]

Black sits in front of the chessboard. It is his turn to move (see diagram):
What can I do he asks? I have developed quickly, my King is safe, I got the pair of Bishops in a relatively open position and my Rooks are centralized and helpful. What does he has? I caught his King in the center and none castle moves are available; still his central forces Qd2+Be3+Nf1+f2 have built quite a fortress there. Hmm, what should I be doing here? If I offer a draw, at least I know White will accept it
Your task: you are Black and should solve the dilemma with the best continuation you can think of.
Total available points for this puzzle is 10. The answers will be published next week together with puzzle #198.

Puzzle #196 solution:
Kotov - Barcza, Stockholm 1952. Surprisingly nobody solved the puzzle all the way to the end. Beside the simpler issues of recognizing a pin and realising what each piece is really doing, finding the key sacrifice was not a problem; the problem was calculating correctly all the way to the end. Leo's answer:
a) Situation analysis:
Material equal;
King safety: white is much better as Black is 100% defending and no piece attacking. Black's King is blocked in the Kingside corner with only one square to go.
Center: Although White pieces push the Black pieces into their territory, Black still has a nice Fianchetto and pawn structure in front of the King.
Pieces: Black looks down by one Knight as Na7 doesn't do anything. And Black's Rf8 and Ne8 got stuck.
b) Explain why the position is ripe:
Because all the Black pieces are cramped in the back with no piece attacking, White has no worry about its King safety. And White has enough attacking power in the position. It is the time to launch the final close combat.
The winning ideas for white:
- Break Black's Fianchetto: use Bishop to take the Bishop inside the Fianchetto (destroy the core of Fianchetto). Fortunately White already has its Bishop in this postion.
- Since Black is well protected by its Pawn structure and many defending pieces, White has no open files for both Rooks; the best attacking routes for White are the diagonals of its Bishop and Queen which are not blocked by any pawns.
- Try to create absolute pin that helps the attack."

Complete solution by Eugen:

[Event "Puzzle #196"][Date "2012.05.07"][Result "1-0"][SetUp "1"][FEN "3rnrk1/n3qpbp/p1pp2p1/1p6/2PNP3/1PB1NPP1/P2Q2KP/3R1R2 w - - 0 1"]1.Ndf5! gxf5 2.Nxf5 Qc7 (2...Qe6 3.Bxg7 Nxg7 4.Qg5 Qe5 5.Nh6+ Kh8 6.Qxe5 dxe5 7.Rxd8 Rxd8 8.Nxf7+ {White wins}) 3.Nxg7 Nxg7 4.Bf6!! Kh8 5.Qg5 Rg8 6.h4 Rde8 7.h5 Re5 8.Bxe5 dxe5 9.Qf6 {White wins}

Correct solutions:
Jeffrey, Leo - 15 points
Philip - 12 points
Ziyao - 10 points
Derrick, Alex, Justin - 8 points
James, Leroy, Daniel - 5 points

Philip - 363 points
Ziyao - 300 points
Jeffrey - 276 points
James - 265 points
Leo - 255 points
Daniel - 241 points
Derrick - 221 points
Alex - 195 points
Leroy - 194 points
Harmony - 187 points
Coco - 184 points
Justin - 112 points
Kevin - 42 points


Advanced pin  (3)