These entities (I am not quite sure if they count as people anymore) are rather worrysome. They should be eliminated as fast as possible before they kill anyone else.
So any ideas on how to kill them without being rendered deaf, burned alive or electrocuted? I am not exactly a professional on Spirits or the abyss.
I am currently classified into not saying why, but Neferyah's allies are more than capable of containing the three of them, and the synthetic skin they were given both lessens the stress that drives the Ravaged to kill to dull the pain, and are effectively straightjackets; for the foreseeable future, all three are bound to containment cells to be studied. [I agree with you on the elimination order, but our current bosses think they can learn something.]
But in case that changes, I will say they aren't really adapted for non-Awakened hunters. They can't attack something they don't see coming, and apart from their burn-carapace, their bodies aren't different enough from baseline humans to be less squishy than a normal physically fit individual. In fact, their vulnerability to toxins-tranquilizers, to be precise-is why they're currently enjoying the housing plan of the subjects of occult research and why Cichol is still alive). The trick is to not fight the Abyss by its rules; if Supernal magic is self-destructive, find non-Supernal magic or a mundane way of overcoming a threat. The Ravaged are powerful, intelligent, and stealthy, but they at least are more shaped by having been human for most of their lives, and not humans who are familiar with survivalist tactics or fighting. They relied more on their superpowers than tactics in a fight, and that plus occult ignorance was how they lost. [Hey, don't forget the woman who dropped that tear gas on them!] (You are covered under "occult ignorance".)
Really, I'm more frightened of Shard Crows. Still compiling, and trying to get a bead on Foetia's link to something called the "Bearers of Fire", but the Ravaged do as they do because of human reasoning. Shard Crows do everything the Ravaged do and more just to reproduce; they are the implacable ones.