The ziggurat, also known as edge template III1-a or template 4-3-2, is a 3rd row edge template with one stone.
It is one of the most basic non-trivial edge templates. The carrier is very small so this template occurs in real games quite often. The small size of the carrier makes it efficient as a threat of template reduction when building other templates. It also appears sometimes in the middle of the board as an interior template.
This ziggurat can be used to prove very easily that a move in the center of a size 5 board is winning.
Defending the ziggurat
Red has two main threats by playing at "A" or "B":
These moves lead to easy direct connection. Because there is no common empty hex used in both threats, Blue cannot prevent Red from connecting to the bottom.