A Chess Lock Puzzle?

Clash Royale CLAN TAG#URR8PPP

up vote
5
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favorite

2

I was recently talking to one of my friends who played chess (much better than me, I'll admit). He said he had a different kind of chess problem, one that may be a little easier, or that may be a little bit harder than usual. He said it was a chess lock puzzle.

He then grabbed two(!) chess sets and set up the following position:

He challenged me to find the least number of moves to capture the black king, using the following rules:

1. White gets an infinite number of moves.


2. White may only capture undefended pieces, and the black king (checkmate isn't a thing, just capture the black king)


3. Rooks are the only keys that work. You must capture the black king with a rook.

He said his best was to do it in 17 moves. Can you do it quicker?

chess

share|improve this question

edited 48 mins ago

asked 1 hour ago

Excited Raichu

2,543231

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Just to clarify, do black's pieces capture whites pieces if they are in a position where they could?
  – gabbo1092
  46 mins ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  @gabbo1092 no, but white is not permitted to capture black pieces that are guarded.
  – Excited Raichu
  46 mins ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  @gabbo1092 I think that black pieces can't do any moves. We only consider white moves. Am I right?
  – Piotr Wasilewicz
  45 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @PiotrWasilewicz yes.
  – Excited Raichu
  43 mins ago
  

  
  
  
  

add a comment | 

up vote
5
down vote

favorite

2

I was recently talking to one of my friends who played chess (much better than me, I'll admit). He said he had a different kind of chess problem, one that may be a little easier, or that may be a little bit harder than usual. He said it was a chess lock puzzle.

He then grabbed two(!) chess sets and set up the following position:

He challenged me to find the least number of moves to capture the black king, using the following rules:

1. White gets an infinite number of moves.


2. White may only capture undefended pieces, and the black king (checkmate isn't a thing, just capture the black king)


3. Rooks are the only keys that work. You must capture the black king with a rook.

He said his best was to do it in 17 moves. Can you do it quicker?

chess

share|improve this question

edited 48 mins ago

asked 1 hour ago

Excited Raichu

2,543231

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Just to clarify, do black's pieces capture whites pieces if they are in a position where they could?
  – gabbo1092
  46 mins ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  @gabbo1092 no, but white is not permitted to capture black pieces that are guarded.
  – Excited Raichu
  46 mins ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  @gabbo1092 I think that black pieces can't do any moves. We only consider white moves. Am I right?
  – Piotr Wasilewicz
  45 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @PiotrWasilewicz yes.
  – Excited Raichu
  43 mins ago
  

  
  
  
  

add a comment | 

up vote
5
down vote

favorite

2

up vote
5
down vote

favorite

2

2

I was recently talking to one of my friends who played chess (much better than me, I'll admit). He said he had a different kind of chess problem, one that may be a little easier, or that may be a little bit harder than usual. He said it was a chess lock puzzle.

He then grabbed two(!) chess sets and set up the following position:

He challenged me to find the least number of moves to capture the black king, using the following rules:

1. White gets an infinite number of moves.


2. White may only capture undefended pieces, and the black king (checkmate isn't a thing, just capture the black king)


3. Rooks are the only keys that work. You must capture the black king with a rook.

He said his best was to do it in 17 moves. Can you do it quicker?

chess

share|improve this question

edited 48 mins ago

asked 1 hour ago

Excited Raichu

2,543231

I was recently talking to one of my friends who played chess (much better than me, I'll admit). He said he had a different kind of chess problem, one that may be a little easier, or that may be a little bit harder than usual. He said it was a chess lock puzzle.

He then grabbed two(!) chess sets and set up the following position:

He challenged me to find the least number of moves to capture the black king, using the following rules:

1. White gets an infinite number of moves.


2. White may only capture undefended pieces, and the black king (checkmate isn't a thing, just capture the black king)


3. Rooks are the only keys that work. You must capture the black king with a rook.

He said his best was to do it in 17 moves. Can you do it quicker?

chess

chess

share|improve this question

edited 48 mins ago

asked 1 hour ago

Excited Raichu

2,543231

share|improve this question

edited 48 mins ago

asked 1 hour ago

Excited Raichu

2,543231

share|improve this question

share|improve this question

edited 48 mins ago

edited 48 mins ago

edited 48 mins ago

asked 1 hour ago

Excited Raichu

2,543231

asked 1 hour ago

Excited Raichu

2,543231

asked 1 hour ago

Excited Raichu

2,543231

2,543231

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Just to clarify, do black's pieces capture whites pieces if they are in a position where they could?
  – gabbo1092
  46 mins ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  @gabbo1092 no, but white is not permitted to capture black pieces that are guarded.
  – Excited Raichu
  46 mins ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  @gabbo1092 I think that black pieces can't do any moves. We only consider white moves. Am I right?
  – Piotr Wasilewicz
  45 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @PiotrWasilewicz yes.
  – Excited Raichu
  43 mins ago
  

  
  
  
  

add a comment | 

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Just to clarify, do black's pieces capture whites pieces if they are in a position where they could?
  – gabbo1092
  46 mins ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  @gabbo1092 no, but white is not permitted to capture black pieces that are guarded.
  – Excited Raichu
  46 mins ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  @gabbo1092 I think that black pieces can't do any moves. We only consider white moves. Am I right?
  – Piotr Wasilewicz
  45 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  @PiotrWasilewicz yes.
  – Excited Raichu
  43 mins ago
  

  
  
  
  

Just to clarify, do black's pieces capture whites pieces if they are in a position where they could?
– gabbo1092
46 mins ago

Just to clarify, do black's pieces capture whites pieces if they are in a position where they could?
– gabbo1092
46 mins ago

1

1

@gabbo1092 no, but white is not permitted to capture black pieces that are guarded.
– Excited Raichu
46 mins ago

@gabbo1092 no, but white is not permitted to capture black pieces that are guarded.
– Excited Raichu
46 mins ago

1

1

@gabbo1092 I think that black pieces can't do any moves. We only consider white moves. Am I right?
– Piotr Wasilewicz
45 mins ago

@gabbo1092 I think that black pieces can't do any moves. We only consider white moves. Am I right?
– Piotr Wasilewicz
45 mins ago

@PiotrWasilewicz yes.
– Excited Raichu
43 mins ago

@PiotrWasilewicz yes.
– Excited Raichu
43 mins ago

add a comment | 

3 Answers
3

active

oldest

votes

up vote
4
down vote



accepted

I think there's a quicker way to do it.

Rb2 Nb1 Rd2 Bd1 Rf2 Bfe2 Rf4 Bgf3 Rg4 Rxg7 Rg8 Rxa8

for 12 moves.

share|improve this answer

answered 32 mins ago

Especially Lime

1,263411

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Yeah, this was it (and this gets the check for the earlier timestamp)
  – Excited Raichu
  30 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  Darn I was just finishing double checking mine and you just beat me! Congrats!
  – gabbo1092
  30 mins ago
  

  
  
  
  

add a comment | 

up vote
2
down vote

I can do it in 15 moves by my count.

The key is to move it around like one of those sliding block puzzles (like rush hour first. Then you only need to get a pawn promoted to a rook. No need to move any existing rooks out.

Spoiler Break

Rb2

Nb1

Rd2

Bd1

Ne2

Nf4

Ne6

Nxg7

Ne8

Nxf6

Ng8

f6

f7

f8=R

Rxa8

And will look something like this (apologies if I mess something up, I set the picture up after the fact, the annotation should be right.

https://i.imgur.com/xZcshmk.png

share|improve this answer

answered 37 mins ago

JGibbers

1,5411518

add a comment | 

up vote
2
down vote

I think I found a solution in 12 moves:

1.Rb2
2. Nb1
3. Rd2
4.Bd1
5. Rf2
6.Be2
7.Rf4
8.Bf3
9.Rg4
10. Rxg7
11.Rg8
12.Rxa8

share|improve this answer

answered 31 mins ago

gabbo1092

2,333428

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  I think you were about 28 seconds behind @Especially Lime unfortunately
  – JGibbers
  30 mins ago
  

  
  
  
  

add a comment | 

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3 Answers
3

active

oldest

votes

3 Answers
3

active

oldest

votes

active

oldest

votes

active

oldest

votes

up vote
4
down vote



accepted

I think there's a quicker way to do it.

Rb2 Nb1 Rd2 Bd1 Rf2 Bfe2 Rf4 Bgf3 Rg4 Rxg7 Rg8 Rxa8

for 12 moves.

share|improve this answer

answered 32 mins ago

Especially Lime

1,263411

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Yeah, this was it (and this gets the check for the earlier timestamp)
  – Excited Raichu
  30 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  Darn I was just finishing double checking mine and you just beat me! Congrats!
  – gabbo1092
  30 mins ago
  

  
  
  
  

add a comment | 

up vote
4
down vote



accepted

I think there's a quicker way to do it.

Rb2 Nb1 Rd2 Bd1 Rf2 Bfe2 Rf4 Bgf3 Rg4 Rxg7 Rg8 Rxa8

for 12 moves.

share|improve this answer

answered 32 mins ago

Especially Lime

1,263411

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Yeah, this was it (and this gets the check for the earlier timestamp)
  – Excited Raichu
  30 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  Darn I was just finishing double checking mine and you just beat me! Congrats!
  – gabbo1092
  30 mins ago
  

  
  
  
  

add a comment | 

up vote
4
down vote



accepted

up vote
4
down vote



accepted

I think there's a quicker way to do it.

Rb2 Nb1 Rd2 Bd1 Rf2 Bfe2 Rf4 Bgf3 Rg4 Rxg7 Rg8 Rxa8

for 12 moves.

share|improve this answer

answered 32 mins ago

Especially Lime

1,263411

I think there's a quicker way to do it.

Rb2 Nb1 Rd2 Bd1 Rf2 Bfe2 Rf4 Bgf3 Rg4 Rxg7 Rg8 Rxa8

for 12 moves.

share|improve this answer

answered 32 mins ago

Especially Lime

1,263411

share|improve this answer

share|improve this answer

answered 32 mins ago

Especially Lime

1,263411

answered 32 mins ago

Especially Lime

1,263411

answered 32 mins ago

Especially Lime

1,263411

1,263411

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Yeah, this was it (and this gets the check for the earlier timestamp)
  – Excited Raichu
  30 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  Darn I was just finishing double checking mine and you just beat me! Congrats!
  – gabbo1092
  30 mins ago
  

  
  
  
  

add a comment | 

• 
  
  
  

  
  

  
  
  
  
  
  

  
  Yeah, this was it (and this gets the check for the earlier timestamp)
  – Excited Raichu
  30 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  Darn I was just finishing double checking mine and you just beat me! Congrats!
  – gabbo1092
  30 mins ago
  

  
  
  
  

Yeah, this was it (and this gets the check for the earlier timestamp)
– Excited Raichu
30 mins ago

Yeah, this was it (and this gets the check for the earlier timestamp)
– Excited Raichu
30 mins ago

Darn I was just finishing double checking mine and you just beat me! Congrats!
– gabbo1092
30 mins ago

Darn I was just finishing double checking mine and you just beat me! Congrats!
– gabbo1092
30 mins ago

add a comment | 

up vote
2
down vote

I can do it in 15 moves by my count.

The key is to move it around like one of those sliding block puzzles (like rush hour first. Then you only need to get a pawn promoted to a rook. No need to move any existing rooks out.

Spoiler Break

Rb2

Nb1

Rd2

Bd1

Ne2

Nf4

Ne6

Nxg7

Ne8

Nxf6

Ng8

f6

f7

f8=R

Rxa8

And will look something like this (apologies if I mess something up, I set the picture up after the fact, the annotation should be right.

https://i.imgur.com/xZcshmk.png

share|improve this answer

answered 37 mins ago

JGibbers

1,5411518

add a comment | 

up vote
2
down vote

I can do it in 15 moves by my count.

The key is to move it around like one of those sliding block puzzles (like rush hour first. Then you only need to get a pawn promoted to a rook. No need to move any existing rooks out.

Spoiler Break

Rb2

Nb1

Rd2

Bd1

Ne2

Nf4

Ne6

Nxg7

Ne8

Nxf6

Ng8

f6

f7

f8=R

Rxa8

And will look something like this (apologies if I mess something up, I set the picture up after the fact, the annotation should be right.

https://i.imgur.com/xZcshmk.png

share|improve this answer

answered 37 mins ago

JGibbers

1,5411518

add a comment | 

up vote
2
down vote

up vote
2
down vote

I can do it in 15 moves by my count.

The key is to move it around like one of those sliding block puzzles (like rush hour first. Then you only need to get a pawn promoted to a rook. No need to move any existing rooks out.

Spoiler Break

Rb2

Nb1

Rd2

Bd1

Ne2

Nf4

Ne6

Nxg7

Ne8

Nxf6

Ng8

f6

f7

f8=R

Rxa8

And will look something like this (apologies if I mess something up, I set the picture up after the fact, the annotation should be right.

https://i.imgur.com/xZcshmk.png

share|improve this answer

answered 37 mins ago

JGibbers

1,5411518

I can do it in 15 moves by my count.

The key is to move it around like one of those sliding block puzzles (like rush hour first. Then you only need to get a pawn promoted to a rook. No need to move any existing rooks out.

Spoiler Break

Rb2

Nb1

Rd2

Bd1

Ne2

Nf4

Ne6

Nxg7

Ne8

Nxf6

Ng8

f6

f7

f8=R

Rxa8

And will look something like this (apologies if I mess something up, I set the picture up after the fact, the annotation should be right.

https://i.imgur.com/xZcshmk.png

share|improve this answer

answered 37 mins ago

JGibbers

1,5411518

share|improve this answer

share|improve this answer

answered 37 mins ago

JGibbers

1,5411518

answered 37 mins ago

JGibbers

1,5411518

answered 37 mins ago

JGibbers

1,5411518

1,5411518

add a comment | 

add a comment | 

up vote
2
down vote

I think I found a solution in 12 moves:

1.Rb2
2. Nb1
3. Rd2
4.Bd1
5. Rf2
6.Be2
7.Rf4
8.Bf3
9.Rg4
10. Rxg7
11.Rg8
12.Rxa8

share|improve this answer

answered 31 mins ago

gabbo1092

2,333428

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  I think you were about 28 seconds behind @Especially Lime unfortunately
  – JGibbers
  30 mins ago
  

  
  
  
  

add a comment | 

up vote
2
down vote

I think I found a solution in 12 moves:

1.Rb2
2. Nb1
3. Rd2
4.Bd1
5. Rf2
6.Be2
7.Rf4
8.Bf3
9.Rg4
10. Rxg7
11.Rg8
12.Rxa8

share|improve this answer

answered 31 mins ago

gabbo1092

2,333428

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  I think you were about 28 seconds behind @Especially Lime unfortunately
  – JGibbers
  30 mins ago
  

  
  
  
  

add a comment | 

up vote
2
down vote

up vote
2
down vote

I think I found a solution in 12 moves:

1.Rb2
2. Nb1
3. Rd2
4.Bd1
5. Rf2
6.Be2
7.Rf4
8.Bf3
9.Rg4
10. Rxg7
11.Rg8
12.Rxa8

share|improve this answer

answered 31 mins ago

gabbo1092

2,333428

I think I found a solution in 12 moves:

1.Rb2
2. Nb1
3. Rd2
4.Bd1
5. Rf2
6.Be2
7.Rf4
8.Bf3
9.Rg4
10. Rxg7
11.Rg8
12.Rxa8

share|improve this answer

answered 31 mins ago

gabbo1092

2,333428

share|improve this answer

share|improve this answer

answered 31 mins ago

gabbo1092

2,333428

answered 31 mins ago

gabbo1092

2,333428

answered 31 mins ago

gabbo1092

2,333428

2,333428

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  I think you were about 28 seconds behind @Especially Lime unfortunately
  – JGibbers
  30 mins ago
  

  
  
  
  

add a comment | 

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  I think you were about 28 seconds behind @Especially Lime unfortunately
  – JGibbers
  30 mins ago
  

  
  
  
  

1

1

I think you were about 28 seconds behind @Especially Lime unfortunately
– JGibbers
30 mins ago

I think you were about 28 seconds behind @Especially Lime unfortunately
– JGibbers
30 mins ago

add a comment | 

 

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