I love these monsters. They seem seriously screwed up, but that's what I love from them.
First, they're incorporeal without any form of incorporeal resistance.
Second, they blind everything in their aura and aren't immune to blindness.
Third, they explose in bright flames and aren't immune to fire.
The result is a monster that can't work with its peers (considering that the only encounter in the Abomination Vaults feature 2 of them).
But... I find that just so funny, I've decided to add an encounter with a big bunch of them. I'll play them scared and scary, with a complete lack of team spirit, casting their aura in the middle of everyone, using Light Flares when they are blinded by their allies, and killing each other in a lemming like chain explosion.
I'm pretty sure my players will hate me but I'll have a lot of fun.