Chess Online

Ver nice puzzle

To control e and g files preventing the black king to cross the second rank. The rest doesn't require a great deal of analysis pretty obvious.
2 stars sound good. .

The key is quite intuitive, as you would not like to let black king to escape to third rank.
Then when you find the beautiful 'Bohemian' model mate 1... Ke2 2.Qg2+ Kd3 3.Qc2# you know you are onto something.

The difficulty may lie on the fact that each black king move to first rank demands different response from white (well almost- there is a minor dual) and calculating all these to conclusion takes some effort.

This was an extremely UGLY puzzle, despite the few pieces.

White has several different wins after the critical first move. There's nothing special about a mate in four from the initial position, and in fact every legal move except 1.Qf3 leads to a mate in less than 10 move!

If there were only one path to mate, this would be an ok puzzle. But take a look at the move list. This wasn't really a puzzle in the classic sense of the word, and it wasn't very useful.

"Probably the low solve rate is due to those who tried sacrificing the queen"

Excellent!  

I agree, it took me a few minutes to see 1.Nf5. I started looking at ways to sac the N with moves such as 1.Kc2, but I could never force the quick mate that way. Then I looked at some Q moves before stumbling on Nf5. Once I saw Nf5, I realised that Black's King's days were numbered.

I thought it was wrong tho because I found so many different ways to mate in 4 that at first I thought I must have miscalculated.

Every legal move except 1.Qf3?? leads to mate in less than ten moves! The only challenge was finding the fastest mate, but unfortunately there were several ways to do that after 1.Nf5

The knight moving backwards stops the king moving up the board,so the first move seems natural enough and if the king goes on the back rank or front rank as you see it ,then using the queen on the second rank up gives the black king only a few squares to move to on one rank ,which again seems logical enough,good puzzle ,it teaches New comers and a reminder to a few seasoned pros how you should look to cut off squares and shoulder the king to where you are going to win the game.

Although there is only 1 correct first move, depending on black's response, there are multiple second and third moves for white that work.
e.g.
1. Nf5 Ke1
2. Qf3 Kd2 (or 2. Qg2 Kd1 3.Nd4 Ke1 [or 3. Ng3 Ke1 4. Qe3++] 4. Qe2++ )
3. Nd4 Ke1 (or 3. Ng3 Ke1 4. Qe2++)
4. Qe2++

Multiple choices for white's third move also exist when black plays 1...Ke2 as well.

A puzzle should have only one correct move for each black response. This puzzle is flawed for that reason.

I did not look at king g1 for black in reply to whites knight f5 so then queen f3 to cut squares down ,same idea as earlier reducing space and options.

If you are tight on the clock, go for the longer mate. It's quicker to play ten moves without thinking than four moves with thinking.

But I think we are missing the true usefulness of puzzles like this. It's not learning the quickest way to pull off one specific mate, since that's a skill you may never need. I mastered the Smothered Mate 25+years before I got a chance to actually pull one off.

Rather, puzzles such as this give us a chance to learn and practice accurate analysis. That's a skill you can use in any game at any time.

Broadly speaking it doesn't matter - you can win the game only once. But there are a couple of points to chess puzzles
1. Exercise of the imagination - especially in game-derived puzzles, and/or into the efficient winding up of a game.
2. puzzles of the 'Chess problem' genre involve a specialized task that you don't often encounter on the chessboard, the positions being somewhat contrived. All the same, the motifs are often valuable in 'game' play, in looking 'outside the box' for winning, or perhaps game saving, ways to continue.