Puzzle of the week #224

Submitted by eugen on

Long mates (5)

Level
5-Queen
Chess Diagram
[Event "Puzzle #224"][Date "2013.04.15"][Result "1-0"][SetUp "1"][FEN "r6k/pp1q1Pr1/7p/3P1pp1/3N4/PP5P/1B5K/4RR2 w - - 0 1"]
White has done the ultimate sacrifice - its Queen - to reach this position. Simply counting the pieces now tells us the sacrifice has been a very bold decision as White has just a Knight and a Bishop for the Queen. Your tasks:
a) Look closer while analysing the position for both sides to decide if the sacrifice was worth it or not
b) Find the best continuation from this point on with White to move

Total available points for this puzzle is 20. The answers will be published next week together with puzzle #225.

Puzzle #223 solution:
Capablanca – Ribera, Barcelona 1935 simul. The answers I got were more or less good and some very good. Here is a selection forming the best answer:
a) Conditions:
#1 Yes, pawns are in front of the King are not moved
#2 No, the h7-pawn is only defended by the King but can be defended by Nf6
#3 No, there is no advanced pawn on e5
#4 Yes, the g5 square is undefended
#5 Yes, a Rook can come into the attack very fast but the two Knights will have to move somewhere else
#6 No, the Queen+Knight combo isn't supported by a Bishop
b) We have a Rook on the open d-file that can sacrifice itself if White needed it to be gone during the process of the attack - can replace #2.
There's an extra Knight on g3 which we could also bring into the attack - can replace #6.
Solution:
[Event "Puzzle #223"][Date "2013.04.09"][Result "1-0"][SetUp "1"][FEN "r1b2rk1/p1qnnppp/1p2p3/2p5/8/3B1NN1/PPP1QPPP/R2R2K1 w - - 0 1"]1.Bxh7+ Kxh7 2.Ng5+ Kg8 (2...Kg6 3.Qh5+ Kf6 4.Nh7#) (2...Kh6 3.Qh5#) 3.Rxd7 Qxd7 (3...Bxd7 4.Qh5 Rfe8 5.Qxf7+ Kh8 6.Re1 {White wins}) 4.Qh5 Rd8 5.Qxf7+ Kh8 6.Re1 Qe8 7.Nh5 Qxf7 8.Nxf7+ Kg8 9.Nxd8 {White wins}

Correct solutions:
Daniel, James - 45 points
Leo - 30 points
Justin - 20 points
Jerry - 12 points

Jerry - 17 points for puzzle #222

Standings:
Daniel - 192 points
James - 187 points
Leo - 134 points
Justin - 116 points
Derrick, Richard - 89 points
Jerry - 42 points
Aditya - 29 points
Alex - 7 points