Hello there! I have a few questions about the Null she encounters, since I couldn't find it in the Bestiary.

--how large are these creatures? (are they humanoid?)
--are they difficult to take down?
--are they able to be followed/perused to where they might return? (or if so, what might alert a Null to someone's presence, and from what distance? Just asking so I might know how it may react to her!