The domains of dwarves have stood against foes many times their size, one
example is with the Gorgon and Khurin-Azur. I was trying to puzzle out a
reason for this and came up with the following. Since dwarves live underground
in caverns and tunnels, attacking them would be difficult at best. So it seems
logical that all dwarven provinces are treated as if they are half fortified.
Laying siege to the province has no effect. The only way to engage the dwarves
is in small parties that can easily be destroyed in the familiar dwarven caves,
therefore attacks are not effective either. Digging races (such as Orogs) are
able to engage the dwarves from below, allowing them to bear a unit at a time
against the dwarves (who get the defensive bonus of their "fortification").
What do you think of this idea? Perhaps it also costs dwarves 2 more GBs to
Rule a province, due to the digging of more tunnels and caverns.

- -Andrew