For ages, Gunahkar and Diemos have watched from the sidelines as Adom's word spread among the oruch. They spread with the strength of Angoron, and the savage wit of Tarien.
The birth of the bloodrage--when rage blossomed in the midst of the Breaking of Mana--was the last straw. Their former gods thirsted for what bloodrage promised. Diemos, far more clever than his partner, saw an opening. Bloodrage he saw, crafted a way into the oruch psyche--one He might use to harness their rage and power. A backdoor, of sorts.
The result is that among the oruch, tales grow of raging warriors falling into a numbing stupor, their fire drained. Their ancestors become a distant memory. Their rage, it is said, drains away as though sucked from a straw. Eventually, these warriors are found babbling, having forgotten everything they once knew.
The transformation is tragic in one sense, terrifying in another. While their minds are shorn through shadow trickery, their spirits remember some of what was forgotten--that core of what is oruch that may never be taken away. These knowing spirits are left to roam the ether, tied to useless bodies as they rage the ethereal to uncover what Deimos stole from them.
How do the oruch know these things? The oruch know because their ancestors whisper, enraged, once an oruch is taken. The ancestors feel such connections intensely, and may send the cry to local oruch, when one of their children is so theft.
It is these rumors that have pushed the oruch away from Gunahkar and his Diemos. As evidence of this phenomenon becomes more widespread, the oruch are not a people to rest on their laurels. Angoron would guide them to a hero's approach--to fight for their clansfolk.
Mechanically, the Howlers are bloodrage oruch with an ethereal template, or other spirit given form. Their spirits are always ethereal, and tend to remain in a state of rage. Their bodies are left on the material plane, numb and staring. Killing one tends to destroy the other.
It is in theory possible to restore a Howler to its body, though this is the vehicle of tale and story, and not something done overnight.