So, I was experimenting with a different pet set-up for 'Nearly Headless Nick".
I was using Gazelle Fawn against his Macabre Marionette (that's not the name of his pet, but I don't recall what it is off the top of my head atm). The idea was that I would use 'Nature's Ward' on myself, turning my Critter into an Elemental, thus allowing me to ignore the 50% reduction in healing caused by his 'Call Darkness'. In theory, this should've enables me to maintain decent heals on myself while also dealing Critter dmg to him.
Unfortunately, this didn't seem to have worked. My heals were still being cut in half. I don't know if this is because he cast 'Call Darkness' before I could activate 'Natures Ward' (so the weather effect was already in place before I 'transformed' myself into an elemental). Or, if it's because Elementals don't gain immunity from the healing reduction. OR... because my pet isn't 'technically' an elemental, and thus not actually benefiting from the class benefit.
Anyone have a speculation on this?