Realms spread like an plague

[Necrisha]

I wouldn't mind fealty cairns being brought back into game as something to build to maintain realm presence at the cost of draining part of the village's presence. That way the realm would decay as villages cease existing. And you need the support of at least one established village in the province to maintain the realm claim for more than a week. You could have a 'fun event' where a very powerful Troll-sized Nidbane pops out of the Thingwall to destroy the fealty cairn after the village looses enough presence that it can't maintain the fealty stone.

Could be a fun event for combat oriented folks as well, if successfully defeating the Nidbane gives some visually thematic stuff to the realm defenders.