Meanwhile, the Shield is behaving exactly as a proper shield should and Defending, raising its already formidable Physical Defense by 10%. It refrains from acting against the rest of the party while it has an axe to grind with Castor, and fortunately, Castor's stats are high enough that her strength can keep it at bay. (Though, it is angling to try to force her off the stairs.)

As far as the group can tell, there doesn't appear to be anything behind the Shield wielding it, and indeed, such a shield would be awfully large to be wielded by a human combatant. It is a mystery....