Difference between revisions of "Cornering"

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(Converted to new hexboard diagrams)
(Added another cornering move.)
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In a [[ladder]] situation when no [[ladder escape]] exists, the [[ladder|attacking player]] can [[ladder]] into a corner and create a "quasi-escape piece" at the very last minute. This play is called '''cornering'''.
 
In a [[ladder]] situation when no [[ladder escape]] exists, the [[ladder|attacking player]] can [[ladder]] into a corner and create a "quasi-escape piece" at the very last minute. This play is called '''cornering'''.
  
Example:
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=== Pivoting ===
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The most common form of cornering is ''pivoting'': when the attacker [[ladder handling|breaks the ladder]] by playing one hex ahead. This usually results in a ladder for the opponent. Example:
  
 
<hexboard size="5x10"
 
<hexboard size="5x10"
Line 19: Line 21:
  
 
Red could have also cornered earlier, resulting, for example, in a 4th row ladder for Blue.
 
Red could have also cornered earlier, resulting, for example, in a 4th row ladder for Blue.
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=== C4 corner move ===
  
 
Given enough space, the attacker can sometimes get an outcome that is better than merely turning the ladder, though not as good as a [[switchback]]. For example, starting from a 2nd row ladder, the following maneuver lets Red move towards the center, rather than parallel to Blue's edge:
 
Given enough space, the attacker can sometimes get an outcome that is better than merely turning the ladder, though not as good as a [[switchback]]. For example, starting from a 2nd row ladder, the following maneuver lets Red move towards the center, rather than parallel to Blue's edge:
Line 46: Line 50:
 
Note that Red's 7 is connected to the edge via [[edge template IV2b]].
 
Note that Red's 7 is connected to the edge via [[edge template IV2b]].
  
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=== D3 corner move ===
  
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Another useful corner move for second row ladders is this:
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<hexboard size="7x9"
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  coords="hide"
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  edges="bottom right"
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  contents="R a6 B a7 R 1:b6 B 2:b7 R 3:c6 B 4:c7 R 5:f5 E *:e2"
 +
  />
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This allows the attacker to [[climbing|climb]] to "*", even without a [[Switchback#Switchback threat|switchback threat]], as follows:
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<hexboard size="7x9"
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  coords="hide"
 +
  edges="bottom right"
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  contents="R a6 B a7 R b6 B b7 R c6 B c7 R f5 B 6:e6 R 7:d6 B 8:d7 R 9:g4 B 10:e5 R 11:f3 B 12:d4 R 13:e2
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            S all-area(a6,a7,i7,i5,f2,e2,d3,c5,b6)"
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  />
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This move has some similarities with [[Tom's move]], although it does not require a [[parallel ladder]]. Note that 5 and 9 are connected to the edge by [[edge template IV2b]]. The shaded area is not required for this move, i.e., it can be occupied by Blue.
 
[[category:ladder]]
 
[[category:ladder]]
 
[[category:definition]]
 
[[category:definition]]

Revision as of 20:29, 31 March 2021

In a ladder situation when no ladder escape exists, the attacking player can ladder into a corner and create a "quasi-escape piece" at the very last minute. This play is called cornering.

Pivoting

The most common form of cornering is pivoting: when the attacker breaks the ladder by playing one hex ahead. This usually results in a ladder for the opponent. Example:

13524

This results in a new ladder, but now the attacking player is defending instead.

9876

Red could have also cornered earlier, resulting, for example, in a 4th row ladder for Blue.

C4 corner move

Given enough space, the attacker can sometimes get an outcome that is better than merely turning the ladder, though not as good as a switchback. For example, starting from a 2nd row ladder, the following maneuver lets Red move towards the center, rather than parallel to Blue's edge:

51324

Blue now has several options, but all of them allow Red to connect towards the center of the board:

11910687

Note how Red's 9 is connected to the edge via a double threat at the cells marked "*". If Blue instead plays 6 on the second row, things are generally worse for Blue:

9876

Note that Red's 7 is connected to the edge via edge template IV2b.

D3 corner move

Another useful corner move for second row ladders is this:

51324

This allows the attacker to climb to "*", even without a switchback threat, as follows:

131112910768

This move has some similarities with Tom's move, although it does not require a parallel ladder. Note that 5 and 9 are connected to the edge by edge template IV2b. The shaded area is not required for this move, i.e., it can be occupied by Blue.