The Chess Problems Thread

[Kyng]

Continuing from the old board: 
http://coffee-house-forum.com/topic/5888344/1/#new

Just post chess problems here . They can be any skill level, from beginner to expert. Also, they don't have to be the usual "Mate in X" or "White to play and win": oddball variants like helpmates and selfmates are welcome here too!

With that said, I'm going to start with today's daily Chess.com puzzle, which is a 'normal' chess problem:
https://www.chess.com/forum/view/daily-p...olkov-1951

It's rather mean, though . Can you spot the trick?

Spoiler

White is still able to castle. He shouldn't do it right away; however, he'll have to do it eventually....

(I took forever to spot that )

[Kyng]

Today's Chess.com puzzle is quite amusing: 

https://www.chess.com/forum/view/daily-p...renie-1981

On the face of it, White appears to have an overwhelming advantage; however, he needs to fend off the imminent threat of checkmate. Can he do it?

[Nick]

Black to move and win:

Hint

The immediate Qxh1 is tempting, but if played, the white pieces can force perpetual check.

Solution

1... Qe4+

2. Kd1 h6

3. Qf4 Qb1+

4. Ke2 Qxh1

[Kyng]

Nice puzzle. I didn't get it in the end, though I was along the right lines. 

Spoiler

Of course, 2. Kd1 isn't forced. There are other options: Kf1, Kf2 or Qe3.

I'm guessing that, if 2. Kf1 or Kf2, then 2...h6 3. Qf4 Qxg2+, followed by 4...Qxh1. Or, if 2. Qe3, then the immediate 2...Qxg2+ is possible, as this move kills the perpetual check threat?

[Nick]

Nice puzzle. I didn't get it in the end, though I was along the right lines. 

Spoiler

Of course, 2. Kd1 isn't forced. There are other options: Kf1, Kf2 or Qe3.

I'm guessing that, if 2. Kf1 or Kf2, then 2...h6 3. Qf4 Qxg2+, followed by 4...Qxh1. Or, if 2. Qe3, then the immediate 2...Qxg2+ is possible, as this move kills the perpetual check threat?

Spoiler

3... Qxg2+ isn't available on Kf1 - rooks move sideways. So instead, just play Bd5, again threatening the same thing; the bishop blocks the rook's view of the back rank.

If the king runs to g1 after this, merely Rxc4 followed by Qb1+ (the rook sacrifice is so white can't block Qb1+ with the bishop, ensuring Qxh1).

If 2. Qe3, then 2... Qxg2+ 3. Qf2 blocks the check and maintains pressure on black's rook; you take his rook, he takes your rook. So instead of Qxh1 right away, trade queens and then play Bxh1.

[Kyng]

Ah thanks, didn't spot that! 

As you can tell, I'm not at my best when attempting chess puzzles on Sunday night .

[Nick]

Ah thanks, didn't spot that! 

As you can tell, I'm not at my best when attempting chess puzzles on Sunday night .

lol, same.

That was the highest rated puzzle I've managed to solve. I think it took me 15+ minutes, but I solved it eventually.

.... only to get over excited, and play the wrong move order, failing the puzzle.

[Nick]

Fired up Chessmaster XI and found this one, "The Feast" from 1897:

White to play and mate in two.

Spoiler

hint

solution

1. Qa2

The arrangement of bishop on a8 and white king on h1 appears to make life hard for White, because it creates the possibility of a discovered check by Black if, for example, the queen moves and allows either ...Kc4+ or ...Ke6+. But this is precisely the sort of deception composers like to incorporate into their problems; the idea is that the solver will see the discovered checks and therefore reject a queen move....But it turns out that the key is with the queen after all.

Black is allowed his bit of fun, but the queen is ambushed behind the rook, and White can trump Black by meeting his discovered checks with discovered mates! The threat is 2 Re3 mate, and the queen move prepares to meet 1...Ke4 by 2 Qg2 mate. Black can stop the threat by 1...d3, but then 2 Rb4 is mate, while 1...e4 is answered by 2 Rb5 mate. The two star variations arise from the other moves of Black's king, 1...Kc4+ allows 2 Rf3 mate (the rook must guard d3), and 1...Ke6+ allows 2 Rb7 mate (the rook must guard d7 and e7). Altogether, White's rook delivers a total of five different mates.

[Kyng]

Nope, couldn't do that one . 

Loved the solution when I read it, though! Great puzzle .

[Nick]

I'm a bit upset at myself for having missed this one, I had just read the concept in a book a few days ago.

White to play

Hint

It looks losing, but the white pieces can force a draw by taking advantage of the fact that diagonal movements cover more ground geometrically.

Solution

1. Kb4 saves the game.

If Black pushes the h pawn to promote, White goes 1... h4 2. Kc5 h3 3. Kd6 h2  4. c7 h8=Q 5. c8=Q+ and it's a draw.

So white narrowly has enough time to force a draw if Black mindlessly pushes his h pawn. Let's try something else

1... Kb6 2. Kc4!

If 2... Kxc6, then White can catch the h pawn and it's a draw. So:

2... h4 3. Kd5! h3 4. Kd6 and we have a similar draw after 4... h2 5. c7

Suppose instead of 3... h3 we have

3... Kc7 4. Ke4! and White will catch the h pawn, drawing.