White mates in 2 moves !

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22 points · 5 comments · view on lemmy.world

5 Comments

haroldstork@lemmy.ml · 2 pts · 257d

Fun!

comfy@lemmy.ml · 2 pts · 257d (2 replies)

I don't know the conventions for these puzzles but I think I've solved it. It's an elegant setup!

::: spoiler spoiler

  • Nb6
  • Only legal moves would be (1) pawn a6, or (2) rook rightwards, up to and including capturing g8+
    • if (1), Ra7#
    • if (2), capture the rook, # :::
lalo@discuss.tchncs.de · 2 pts · 257d (1 reply)

!Nb6? Even if you meant Nb7 or Nb5, then black Rxg8+ followed by white's Rxg8+ is not mate in 2. I duplicated the ponies so it's easier to see, even in this position is not mate Position in question!<

comfy@lemmy.ml · 1 pts · 252d

Whoops, I meant Nb5, and you're right, I was mistaken.

Now that I've had some proper sleep: How about Nc8? Black can't move the king, can't use the rook to threaten white's king, moving the pawn forward would expose Ra7#, and using the rook to capture would allow Rc8#

jxk@sh.itjust.works · 1 pts · 243d

The solution is Nc8.

This is actually an easy one to find out. Here's how I solved it: You can see in the given position, if black was to move, black could play Rxg8+ with check. This means that, if black is allowed to play Rxg8+ after white's first move, then white is in check, and will not be able to mate on the second move. Therefore, white's first move must make Rxg8+ impossible. The only four moves that do the trick are Nc8, Ne8, Rxb8+ and Kh7 (Kh7 doesn't avoid Rxg8, but makes it a non-checking move). Out of those, it's easy to check that only Nc8 works.

  1. Nc8
    1. ... a6 or a5: 2. Ra7#
    1. ... R to anywhere on the B file: 2. Nb6# (with double check)
    1. ... Rxc8: 2. Rxc8#