Ladder handling

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In a ladder situation, the players have two different roles: The player who tries to connect to the edge is called the attacker, and the player who tries to prevent the other from connecting is called the defender. Here is an example where Red is the attacker and Blue is the defender, with Blue to move.

Generally the attacker has the initiative. The defender's moves are usually forced; he has to defend or else the attacker will connect.

Defending

The defender usually has two options: he can push (a) or he can yield (b). The possibilities are shown in the following diagram:

ab
  • Pushing means to play a move on the same row as the earlier moves.
  • Yielding means to allow the attacker to get one row closer to the edge.

It is usually best to continue pushing until the attacker does something else, but occasionally it is essential to yield in order to avoid one of Red's outposts, as in the following situation:

ab

If Blue pushes in this diagram, Red will be able to connect to the bottom using edge template IV2b. If Blue yields instead, Red won't be able to connect within the area shown here. (Whether Red can connect anyway depends on what is going on elsewhere on the board; for example, Red may have a nearby ladder escape, may be able to climb, or may have enough space to play Tom's move). It is important for Blue to yield at precisely the right moment. Had he done it one move earlier, Red would have been able to connect to the bottom.

Note that in case of a 2nd row ladder, Blue's only option is to push. For 3rd row ladders, Blue's options are to push or yield. For 4rd and higher row ladders, Blue has additional options; see Theory of ladder escapes for a more detailed analysis.

Attacking

Red usually has three options: she can push (a), jump (b), or pivot (c). The possibilities are shown in the following diagram:

bac
  • Pushing means to continue with adjacent moves on the same row.
  • Jumping means to go one row further away from the edge. Note that jumping is a move similar (symmetric) to the defender´s yielding; however jumping is usually an offensive move, while yielding is very defensive, hence they have different words.
  • Pivoting or breaking means to play on the same row, but skipping one hex.

Jumping is used when the attacker has a ladder escape but needs to get further from the edge to use it. Here is a standard example:

Red first jumps to (*). If Blue makes the standard response, Red's next move is (+), making a connection to the bottom via a trapezoid and a ziggurat.

Other options

  • Jumping is also an option for the defender, where he allows the attacker to connect in exchange for important territory. This usually happens when the attacker already has a ladder escape and is sure to connect, but the defender wants to get the most compensation out of his position. The most common way to jump is on the same row as the attacker's ladder and skipping a hex:
12
  • Cornering is an option for the attacker when she doesn't have a ladder escape.

Examples

In the following game, Red needs a ladder escape to the bottom ladder:

abcdefghij12345678910

Red can get this by jumping to the 3rd row:

abcdefghij1234567891012

Because now i8 is a working ladder escape fork:

abcdefghij12345678910132