Some shielded drones you encounter in N'erud first over world start at less than full shield strength (their shield bar is partially full). The issue isn't something like Vile spreading negative status effects and softening them before you encounter them. It happens just when you spawn at the world stone and the first thing you encounter is a shielded drone. I'm playing on Survivor.
#Shielded drones in first N'erud over world start at less than full shield strength
outer flint
narrow bone
Noticed this as well. This happens in Nightmare as well.