Daily Chess Puzzle

Today’s problem was seen on Twitter a month or two ago. If I recall correctly, GM Simon Williams tweeted it as a teaser for one of his forthcoming shows. I took a screen shot, and enjoyed solving it whilst walking up Castle Crag in Borrowdale recently. The joy of chess is that no equipment is needed.

As is my custom, I only say which side is to play: and not giving an idea if the move wins or otherwise, unless on occasion I think signposting would be helpful. Instead, the problems are posed with the instruction to decide what you would play, as in a game.

White to play

unknown, might be a composition

Solution

The solution is a series of steps.

Stage 1: lock in the Black king with the N, so that the White king can move.

1 Kf7 (stopping …Nf6, so freeing White’s knight) 2 Ne3 3 Nf5 4 Nd6 5 Ne8

Black to move

Stage 2: lose a move by triangulating the king

The Ne8 stops the Black king getting out, and also prevents Nf6. The only square the N doesn’t protect is e7, so White’s king must stay next to that square, to stop the Black knight escaping.

Fortunately there are three squares -d7-d6-e6- so White can get back to f7 with it being White to move.

6 Ke6 7 Kd7 8 Kd6 9 Ke6 10 Kf7

Same position as before, but with White to move.

Step 3: create zugzwang

11 Nc7 12 Ne6 13 Nf8

The Ng8 must move, and is captured, when the win is trivial.

Very nice.

FEN

5Knk/8/7p/7P/6N1/8/8/8 w – – 0 1