Chess Online

Almost one hour and many mistakes. One of the toughest one in this section. Good luck to everybody
4.5 stars

I thought yesterday's (puzzle #32379) was possibly the hardest that I've managed without a mistake on Gameknot, because of all the queen moves and the independent variations you have to consider. The methodical approach that I always try to use was not especially useful. Even after essentially giving up and guessing right on the first move, I still felt a bit lost.

I wouldn't call today's puzzle easy, but it was at least possible to identify a main idea using logic rather than brute force analysis. The clues in the position that helped me were:

(1) Black's king's in a cage, but currently has three squares (d4, e3, e4) inside the cage;

(2) White's dark square bishop isn't doing much. It's pinning a pawn, but White would find it easier to mate if that pawn advanced (e.g. 1. Bg5 e4 2. Bf6+ Ke3 3. Rxc3#);

(3) White's light square bishop also isn't doing much, but it could become a very powerful piece without moving if Black's d5 pawn went somewhere else;

(4) White's pawns, king and R-f1 contribute to the cage and probably can't be improved, but White's R-c7 only contributes to the cage through its control of c5, which happens to be on the same diagonal as d4 and e3.

The twin ideas of the sacrifice Rc4 and getting the dark square bishop on the g1-a7 diagonal naturally follow from this. Playing an immediate 1. Rc4+ looks unpromising, and b6 is the only accessible square on the diagonal that is neither attacked by Black nor interferes with the action of a rook.

Therefore, 1. Bd8 is the first candidate move to analyse. That analysis is far from trivial, and there are a few interesting variations (one of which involves improving the king after all), but it certainly didn't make my head swim like yesterday's.

Nice puzzle!

and we can tell you why the pawn didn't take your rook (it depends on which line your were in), but the general answer is that taking your rook wouldn't have prevented or slowed the mate.

Another way to get an answer is to click on the puzzle, then hover over Options, then click All Moves Graph... once you've solved the puzzle.

I started the puzzle over and over again and was often fooled... especially the first time  
thanks for the puzzle