21/11/20 Puzzle: Solution

In this puzzle, white checkmates in two moves.

Congratulations!

Thank you to everyone who sent in their answers. You received at least 1 point. If you correctly guessed the first move, you received 2 points. If you sent in at least one full solution you got 3 points, and you received a further point for each correct variation on the solution.  This week, the following players received 3 or more points for their solutions:

Rob (4)
Aathiran Oyalood (5)

The current top 3 scorers are:

Aathiran Oyalood (18)
Rob (17)
Earl (13)

This Week’s Solution

The hardest part of mate in two puzzles is to find the first move. In this position, black is about to promote a pawn. This would be disastrous as even an unsafe promotion (to a queen for instance) would be check, and much harder to recover from in our final move which must be checkmate! How to stop black promoting? Check the king – keep black busy. The only other option may be to block the pawn from promoting, but alas, it does not lead to a checkmate.

Finding the correct check is no easy feat. There are five checks to consider in this position. Lets consider the black kings’ field from the current position. e5, e3 and d5 are all options for black. If we look at a two-move range, the king could access the following additional squares: d6, c6 and even e6 as the rook is unguarded. The white king is keeping him penned in from below, but the black king could escape upward.

A check from the queen does not help control any of these squares from move one. Rh4+ and Rf4+ do not help particularly either apart from Rf4+ guarding the rook but instead unguarding the knight. The knight moves, Ng5+ and Nc5+ look more promising – opening the line of the rook along the sixth rank (and therefore allowing control). Both these moves would therefore limit the King’s two move range to just four initially noted squares, e5, e3, d5 and e6, however they would both release a further square of escape. The knight currently controls the square c5, and moving the knight relinquishes control.

In that collection of squares, there are many e’s and many 5’s. The many squares on the fifth rank can easily be covered together by shifting the rook to h5, which would be blocked if the knight moved to Ng5+, so it makes sense to first consider Nc5+.

If after Nc5+, Ke3, the black king is broken off from all other escape squares. The rook on f5 is no longer needed to control the upper ranks, and can be brought down. Rf3++ is checkmate. Note that Rh3+ is only check, as it can be blocked by the black knight.

Things are more challenging if the black king goes upward. If Nc5+, Ke5, the black king has two escape squares, e6 and c5. e6 can be covered by shifting the white king, releasing the queen, and perfectly, the king can be shifted to c4, defending d5. Kc4++ is therefore the solution after Ke5.

If instead Nc5+, Kd5, all the remaining escape squares are on the fifth rank, and our initial idea of bringing the rook upward will cover them all. Rh5++ is the solution. It is important that the rook on f6 is left to cover the sixth rank whilst the unused rook in the corner takes on a new role.

A maximum of five points were offered this week. 3 points for any solution after Nc5+, and 2 additional points for the further solutions.

It is not unusual to struggle with checkmate in twos! The visualisation skills necessary to complete these are advanced, making them much more challenging than the checkmate in one puzzles. You have to hold two pieces in different positions in your mind AND still consider a third move. Focusing on the kings field (the 8 squares surrounding the king) and keeping track of how (and if) it changes is invaluable! Also, make sure to double check your solution with move/capture/block.

If you struggled, you can make it easier by setting up the position on a board and moving the pieces around, but remember that in a real game you cannot get away with this behaviour! It is important to build your visualisation skill up so you can better see through your plans on the chess board. If you would like to practice your visualisation skills further I would recommend studying Sharpen your Skills or Visi-Power.

What To Do Next

Tomorrow you will be able find next week’s puzzle on our blog. The puzzler with the highest score at the end of the block will win a free chess lesson with the teacher of their choice and a solver badge and spot/two solver spots. Our runners up will receive a solver badge or a solver spot if they already have a badge. Consistently sending in your results is key to winning so make sure you subscribe below to get notified about the checkmate puzzles the moment they are published.


Diagram courtesy of www.chess.com


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: