Can you find the checkmate in 4 for White?
Puzzle by Speckmann, presented by Andreas
8/8/7R/8/8/KPP4b/2B5/k7 w – – 0 1
Chess Daily News from Susan Polgar
Checkmate in 4
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1. Rh5 Bg2
2. Re5 Bf3
3. Re1+ Bd1
4. Rxd1#
1. b2 ++
White cannot take the bishop because of stalemate. So:
1. Rd6 Bg4 The bishop must cover square d1 and cannot move between the rook and the first rank.
2. Rd2 Bh4/f3/e2
3. Bh7 and now
4. Ra2# is unstoppable.
1. Bh7! and now:
1… Bg2 2. Re6 Be4 3. Rxe4 Kb1 4. Re1#
1… Bf1 2. Rh2 Bg2 3. Bd3 Bf3 4. Ra2#
2. … Be2 3. Rh1+ Bf1 4. Rxf1#
This one was tough.
1. Bh7! Bg2 (alternative below)
2. Re6! Be4
3. Rxe4 Kb1
4. Re1++#
1. … Bf1
2. Rh2! Bg2 (Bd3? Rh1+ Bb1 Rxb1#)
3. Bd3! any (zugzwang)
4. Ra2#
This is way too hard.
Black bishop must go between f1 and h3, other wise Rh1 (then if necessary RxB) mate.
1. c4 (to prevent bishop from checking white king)
2. b4 (to ensure white king to go to b3)
3. Kb3
4. Ra6 or h1 mate (according to position of black bishop)
Bh7
Hello: Maybe 1.Rh4 Bg2 2.Rg4 Bf3 3.Rg1+ Bd1 4.Rd1++
Thank you for your blog Susan. I am a new supporter
Hello: Maybe 1.Rh4 Bg2 2.Rg4 Bf3 3.Rg1+ Bd1 4.Rd1++
Thank you for your blog Susan. I am a new supporter
Hello: Maybe 1.Rh4 Bg2 2.Rg4 Bf3 3.Rg1+ Bd1 4.Rd1++
Thank you for your blog Susan. I am a new supporter
Hello: Maybe 1.Rh4 Bg2 2.Rg4 Bf3 3.Rg1+ Bd1 4.Rd1++
Thank you for your blog Susan. I am a new supporter
My last comment is not correct.
I continue tinking.
An interesting puzzle. Because the black king is immobilized on a1, black can use the bishop to block the rook’s access to the 1st rank if the rook is on h6, g6, and f6- the bishop can only be taken on the first rank without stalemate. In addition, black can take the rook at e6, h1, f1 and d1 since the problem is a mate in 4, not just white to win. So, at the outset, white must be looking for either a pawn move, a bishop move, or a king move. I think the king must stay on a3 since I don’t see how you dislodge the black king from b2 if you allow him to play there, so we are down to pawn moves and bishop moves at move 1.
Now, 1.Bf5 catches the eye for a moment, but black can just capture and block the check with Bb1 to avoid the mate in 4 easily.
One idea with the pawn moves is to clear the b-pawn and/or the c-pawn out of the way so the rook can get to b1, but this seems to take too long:
1. b4 Bf1
2. c4 Bg2
3. Rf6
I looked at this for quite a while, this is as short as I can find for white, and now black can play either Bh3 or Bf3 ensuring white can’t mate in less than 5 moves total.
So, can we play 1.b4 with Kb3 and mate on the a-file with the rook? I don’t think so since the black bishop can harass the king when he is on b3:
1. b4 Bf1
2. Kb3 Bc4
3. Kc4
If 3.Ka3, black gets beyond the 4th move with Bd5 guarding h1 again. Continuing:
3. …..Kb2 (or Ka2) and black is going to survive the 4th move to beat the problem.
So, we are definitely looking for a bishop move on move 1. But which one? If white plays 1.Bb1, I think black can safely take it since I don’t see any mate in less than 8 or 9 moves minimum since the king just escapes the trap on a1. In addition, playing 1.Bd1 seems to let the king escape, too, long enough to beat the problem:
1. Bd1 Kb1 (not the best move)
2. Rh3 Kc1
3. Rd3 Kb1 and I can see a mate in 6 total, but this is not the solution.
So, the first move must be either Bd3, Be4, Bg6, or Bh7 (we eliminated Bf5 earlier). Let’s take them in order:
1. Bd3 Bf1!
The main idea I have for moving the bishop is to get the rook to a2 for a mate, so black cannot play Bg2 here because 2.Rh2 leads to mate in 3 moves total from the beginning. Now black has defeated the problem since white
2. Bf5
Of course, 2.Rh2 doesn’t win quick enough after black takes at d3, and white can’t pin the bishop with 2.Rh1 without stalemating black. Continuing:
2. …..Bh3 (simplest)
And we don’t need to go further in this line since it is clear black cannot mate in 4 or less in this line. I can see the solution now. If white plays 1.Be4 or 1.Bg6, black will play 1. …Bg2 with the plan of playing Be4 in response to 2.Rh2- white won’t be able to take the bishop at e4 (with the bishop!!) without stalemating black, and white won’t be able to capture the bishop at g2 without allowing the king to escape the hole on a1 long enough to beat the problem. However, if white plays 1. Bh7…..
1. Bh7 Bg2 (alternatives below)
2. Re6! and now black can’t prevent Re1#- if black blocks with Be4, white can take with the rook without stalemating black, and still mate by move 4 with Re1. The only other block is to play 2. …Bf3, but white still mates in 4 total. As for the 1st move alternatives:
1. Bh7 Bg4
2. Rh1 Bd1
3. Rxd1#
1. Bh7 Bf5
2. Rh1 Bb1
3. Rb1#
And, finally….
1. Bh7 Bf1
2. Rh2! Bg2 (Be2 3.Rh1)
3. Bd3! and 4.Ra2# is unstoppable.
1. Bh7!
Forced moves to avoid mate in h1 are
1. … Bg2 or Bf1
if 2… Bg2
2. Re6 Be4 (to avoid Re1#)
3. Rxe4!(Bxe4=)Kb1
4.Re1#
if 1… Bf1
2. Rh2 Bg2 (to avoid Ra2#)
3. Bd3 bishop has to move but cannot block Ra2 now
4. Ra2#
1.Bh7 and the rest you know what it means 🙂
Its not that hard. First Rg6 followed by a few stutter steps and its over.klikti
Rh4 … Bishop moves .., Rf4 or Rd4 … Bishop can take bishop or block rook… Check with rook … Bishop blocks or takes… Check again or b2 to checkmate
1. Rd6 (threatening Rd1#) Bg4
2. Rd2
If 2…Bf5, then 3. Rd1#
else, white can move bishop along the b1-h7 diagonal and deliver mate with 4. Ra2.
This was difficult. I think the right way is:
1. b4! Bd1 (what else?)
2. Kb3!! Bxc2
3. Kxc2 Ka2
4. Ra6+#
To Anant:
1. Rh5 (or any move in h file) Bg2
2. Re5 Be4!
Black will take any opportunity to sack his bishop since it is stalemate always.
To fajac:
1. Rd6 (interesting idea) Bg4
2. Rd2 Be2 (only playable try)
3. Bh7 Bd3!
Interposing bishop in this diagonal is a basic idea for black here!
4. Ra2+ Kb1
or
4. Bxd3 stalemate
or
4. Rd1+ Bb1
To J.P. Trigueros:
You missed that black also has Bf1 since pinning it with Rh1 would be a stalemate.
The idea b4, Kb3 and Ra6# looked interesting, but with the stalemate problem still there, black has plenty opportunities to interpose his bishop somewhere and make this also more than 4 moves.
So only working plan here is 1.Bh7 with the two options 2.Rh2 and 2.Re6 depending on black’s answer.