What’s a great puzzle or brain teaser you know? Explain the puzzle, then write one or more hints (if applicable), then write the solution.

___________

Tim’s puzzle:

Yesterday, my nerdiest friend texted me this chessboard, along with this message: “It’s a chess puzzle. It’s white’s turn and they can get checkmate in two moves. The solution is unbelievably elegant.” (White is moving up on the board.)

I’m really good at Scrabble. I’m okay at crossword puzzles. I’m very, very bad at chess. Maybe I just haven’t played enough, but nothing makes me feel dumber than chess. When I play, I always feel like I’m blindfolded with a bat trying to swing and hit a piñata somewhere.

So I stopped everything and spent 45 minutes trying to figure this out, keeping in mind that the solution was “unbelievably elegant.”

With a slight hint, I eventually got there. If you want to give a try hintless, now’s the time.

HINT:

Pretend you’re black player and it’s your turn. What would you do?

SOLUTION:

The key is that black is in a very fragile position. Almost all of black’s pieces have to stay exactly where they are to avoid handing checkmate to white. The only black piece who can freely roam is the pawn on C3—so all you have to do is use the first of your two moves to block that free pawn, by moving the E4 bishop to C2, and that leaves black with no option then but to walk into checkmate. Let’s go through black’s options after white moves the bishop:

1) Move the king to D6 or D5 (anywhere else is illegal because the king puts himself in check). In either case, the white queen moves to C5 for checkmate.

2) Move the knight on E2 anywhere. This leaves D4 unprotected. White’s queen can move there for checkmate.

3) Move the pawn on C6 to C5. The F4 rook can move up to F5 for checkmate. (Thank you to commenter Owen Griffiths for pointing out the error in this item in the original post.)

4) Move the D7 pawn to D6. This blocks the black king from moving to D7, allowing the F4 rook to move to F5 for checkmate.

5) Move the D7 pawn to D5. This allows white’s queen to move into an unblockable path to the king for checkmate.

Black has no other legal moves. The C3 pawn and H6 bishop are blocked from moving by other pieces, and the G7 rook and G5 knight can’t move without putting their own king into check.

What my friend thought was so satisfying about the solution is that white doesn’t have to do any attacking to win. He just has to block black’s one free piece and then sit back while black defeats himself.

So there you go. Chess is easy after all.

P.S. Another puzzle I put on WBW once

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