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Abnormal Wolves
As noted earlier, the precise shape of the ⚟ can matter in some cases. Abnormal wolves form where there exists within ⚟, a point that is neither a liberty of the surrounding stones, nor a vital point for making two eyes. In this case (3, 2), (3, 2, 2), (4, 2) and (4, 2, 2) are possible, as is (3, 1) when the 1 is not a tail of the abnormal block. The shapes to consider are block-4 on the side and corner, and bent-4 and bent-3 in the corner.
Bent-3 in the corner gives only (3, 2) and (3, 2, 2).
Block-4 in the corner, where ⚟ has only three liberties, behaves as a normal
wolf-n(4) unless there is a tail on the block-4. This case is only stable when the defender can find a ko threat.
For block-4 on the side, Wolf-3(4, 2) and Wolf-4(4, 2, 2) are only stable if the defender can find two ko threats and make one approach move.
Bent-4 is the most complex, with kos in all forms. Bent-4 capturing a tail of 1 wins unless the opponent can find two ko threats and make two approach moves. Capturing a tail of two looks worse than capturing the block, which leads to a ko where the defender must find the first threat. However the defender can strike first, and create a ko where again, they must find the first threat. There sometimes are opportunities to offer a balanced result within the move sequence, and also the question of whether it matters at which end of the bent-4 the tail is.
The interactions between these abnormal wolves is left as an exercise.
On a side note, wolf-3(5, 2+) is stable. The defender places a stone inside allowing the tail to grow again. The ‘2+’ refers to a tail that can grow immediately into a place that has liberties on all sides.
Also, the wolf-4(3, 1, 1) on the previous page is of a form exceptional to the large tail rule.
Wolf-3(6, 2+i) Wolf-3(6, 2+i) and Wolf-3(6, 2+) can also form.
This wolf-3(5, 2++) has a larger tail.
This wolf-3(3, 2~) has a tail 2 longer.