Puzzle of the week #192

Submitted by eugen on Sun, 04/08/2012 - 23:47

Interference (2)

Level
4-Rook
Chess Diagram
[Event "Puzzle #192"][Date "2012.04.08"][Result "1-0"][SetUp "1"][FEN "k3N3/p2p3P/8/2p5/K1pbP3/6q1/P2P4/1R6 w - - 0 1"]
Study positions are in general based on invented positions one cannot normally see in a real game. However their value cannot be considered lower; a study position could contain a perfect example of how a certain procedure works, helping you understand it better. Once you understood it better, the challenge will be to recognize it (if it appears in your games), or even to plan for it in your quest to win the game. This position is from a study: the White pieces are placed in unusual positions. Your tasks:
a) Analyse the position and propose plans for both sides
b) Having the White pieces decide on the best plan of action to win the game

Total available points for this puzzle is 20. The answers will be published next week together with puzzle #193.

Puzzle #191 solution:
S. Loyd - C. Moore, 1860. I did not notice the easy win possible when I chose the puzzle and the book did not say a word about it either. I sent out warning messages asking for another look after posting it and only 2 of you made the effort to look beyond the obvious. They are Derrick and Philip; thank you to both of them for their effort! See the simple and easy win using "blocking" as part of the solution.
Here is now Philip's requested answer:
a) Since blocking is not what you are looking for, I need to do the interference instead. "Qe6" interferes Black's defense ("Bc8" + "Ra6") and White can get a win from this point on
b) See solution
c) In this case, it is easier to win this way. But sometimes, when the King is surrounded by defenders, those defenders are also blocking the King and limit the King's space. So, it could be easier to win when opponent's king surrounded by defenders

[Event "Puzzle #191"][Date "2012.04.03"][Result "1-0"][SetUp "1"][FEN "2br4/1pn3pk/r7/p3N3/2Q2p1N/7R/Pq4PP/4R2K w - - 0 1"]1.Qe6!! ({Missed line in the book} 1.Nf5+ Rh6 2.Rxh6+ gxh6 3.Qf7+ Kh8 4.Qg7#) 1...Bxe6 (1...Rxe6 2.Nhg6+ Kg8 3.Rh8#) 2.Nf5+ Kg8 3.Ne7+ Kf8 4.N7g6+ Ke8 (4...Kg8 5.Rh8#) 5.Rh8+ Bg8 6.Rxg8#

Correct solutions:
Philip, Derrick - 23 points
James, Leo, Ziyao, Leroy, Justin, Coco - 5 points

Standings:
Philip - 267 points
Ziyao - 216 points
James - 201 points
Harmony - 187 points
Jeffrey - 185 points
Daniel - 168 points
Leo - 162 points
Derrick - 159 points
Coco - 140 points
Leroy - 135 points
Alex - 126 points
Justin - 32 points
Kevin - 27 points