The red stone has a certain connection to the bottom, using only the shaded hexagons, even if blue moves first.
Countless edge templates can be constructed, all of them of varying degrees of usefulness and frequency of occurance.
If you want to know more about templates, you could start by learning about Edge templates with one stone. There are some templates here that every good player will know.
Template lists by row number:
Pages in category "Edge templates"
The following 45 pages are in this category, out of 45 total.