For a run down on the critters:
They are not cursed/undead (HE did not work on them, neither did bless).
They are not skinnable.
They do drop coins and gems, I didn't see box drop.
Hunt works
Spawn wasn't great or terrible. Not swarmy for me.
No armor/weapons
They don't hide/stalk
No apparent weapon immunities or resistances
Not all of them seem to spawn with stones? But the rocks are LT/MB with poor in everything I think. It seems like they can forage or pick up rocks, but only throw (I never had one bash at me).
They throw rarely, not constantly.
Thrown rocks appear to be normal attacks, not special attacks?
I could see no change in room name, no obvious barrier, no change in the imps themselves to determine which tier I was in other than appraisal, which I think is intentional.
All in all, a useful critter that will fill helpful gaps, but I think will be under utilized because of the simply torturous entry mechanics and the lack of skinning. That's a long range to have to either train somewhere else, back train, or pick up via teaching.
