As far as demiplanes go, Eustacius is not very large. It is more of a plane of thought, rather than
physical substance; a set of several dozen realms which are interconnected by concepts rather
than actual pathways.
A city the heroes visit is in a crisis, the king and queen are getting a divorce. Who shall rule? The inhabitants of the city take sides by tying a red or blue ribbon to their swords, sticks etc. Whose side will the Pcs take?