Board Thread:The Last Sovereign Discussion/@comment-27713488-20180114010136/@comment-27104094-20180117133639

Giant chicken or lizard legs.. Baba Yagga Hut.

if you had a flying fortress you will not call it a roaming fortress (unless nobody saw it and you want to keep the secret).

other possibility  a Giant turtle swimming (that would also explain the land saw by a succubus) with possible land locomotion too. The Corrupt skill can be used to control it (or he or she hard question for teratologists). Why a turtle because I'm also a Pratchett's fan.

A more stealthy fortress could be inside a giant whale, the succubus saw it when she went at the surface for breathing.

The name of Blood lord inspires me some possible sanguine control of monsters (but I may be wrong).