The Foulands of Mortu - the hag Graeae's domain - has some unique defenses. There is a miasma surrounding the coven-state that infects any living beings passing through it with a deadly wasting disease. Consequently, by the time any forces make their way to Graeae’s door they are dead enough that the hag-queen merely uses her necromantic powers to take control of them and add the dead bodies to her own armies.

The only way to access the Foulands capital of Greyhollow is through a maze of underground tunnel-canals just big enough for ships to pass through. Only mariners such as you know the way through these tunnels, and you have learned over the years that servants of Graeae will occasionally use spells such as Mold Earth to close off some arteries and open others.