Aetherials

''Foolishly and greedily did the arcanists of Cairn delve into the magical veil known as the Aether, never once suspecting that something was looking back. ''

''The Aetherials descended upon Cairn in what is now known as the Grim Dawn, possessing countless humans and butchering the rest. Most despicably of all, they began raising the fallen as mutated undead creatures, mindless foot soldiers for their invasion. Their very presence on Cairn is enough to mutate the wildlife, turning once docile creatures into vicious monstrosities. ''

But most strange of all is their apparent hatred for Chthonians, as they will battle against the horrors from the Void at every opportunity. Aetherials are one of two otherworldly factions present in the Grim Dawn universe. Killing Aetherial and Aether Corruption enemies will increase the players' negative Faction Reputation.

Quotes

 * "What is an Aetherial really?" - Player
 * "We were the servants of the primordial gods, but when our makers grew jealous of one another, we became soldiers in a cataclysmic war. Countless creations were eradicated by the ensuing conflict, countless millennia of our work erased in a flicker of godly anger. But none of that compared to the day one side chose to harness the darkness of the void in a desperate bid for victory. The results were catastrophic and our masters were cut down or scattered to the far reaches of creation. And we, the most loyal servants, were banished to the Aether for the simple crime of serving without question. There, stripped of our physical forms, we were forced to wander the emptiness of the stars for all eternity, the scars inflicted upon us by the void's minions still burning deep. That is until we encountered humans..." - Anasteria
 * "What changed when you found us?" - Player
 * "Human ingenuity...and greed. Your base desires to seek out power are only matched by your ability to adapt and manifest that power in impressive displays. It was the reckless actions of the first arcanists that drew us to this world and it was our whispers that taught your people how to first tap into the limitless potential of the Aether. All it took was a push in the right direction. We had to be patient, but eventually enough of us were able to breach the veil and take matters into our own "hands" and prepare for the Glorious Dawn that would see all Aetherials return to the physical realm. But our actions were not without consequence. Though Chthonian worship was not a new prospect on Cairn, desperate humans made willing allies for the powers of Ch'thon and so an old enemy has returned to haunt us and may well spell doom for us all. Even now as we slaughter one another, the void feeds upon the spilled blood and grows to envelop all of creation." - Anasteria

Possession
Aetherials have the ability to possess living creatures, notably including humans, taking control of the creature's body and mind. A creature possessed in this manner may be referred to as "vessel", and the survivors of the Grim Dawn referred to people lost in this manner as "Taken". This name was later used to refer to a single person who survived possession and became a key character in the resistance efforts against Aetherials and other forces endangering the humans of Cairn.

Possessed humans may or may not be distinguishable from those not hosting an Aetherial. Some vessels, human and not, have had their bodies distorted to various extent, which is immediately recognizable. Some humans have only the distinctively non-human voice and the bluish-green aether-colored glow coming from their eyes. Some others are just like ordinary humans in looks and voice, and detecting them as Aetherials requires unusual means, such as the presence of another Aetherial-possessed human.

An unusual and unanticipated (by Aetherials) side effect of human possession is that the Aetherial is influenced by the mind and emotions of its host. Such influence may even affect the Aetherial's motivation to the extent it chooses to side with the human resistance against the Aetherial invading force. At least two such cases are known. Anasteria, though highly distrusted due to her demeanor and use of controversial magic, provided valuable intelligence to the Black Legion. Korinia eventually became the leader of the Malmouth resistance.

Apparently, negative characteristics of the host's mind affect Aetherials as well. Warden Krieg certainly retained some of his behavior back from his time as the Devil's Crossing warden (for which he was admonished by his Aetherial superiors), and Theodin Marcell's creation of the Fleshworks is likely influenced by his former work as a surgeon.

An even more unusual and unanticipated side effect of human possession are those related to that possession is, in rare cases, reversible. After Sahdina, Jarvis, and John Bourbon interrogated a "Taken" that passed through the riftgate to Devil's Crossing, they hanged it. The Aetherial fled its vessel, and Bourbon had the human cut down. The "Taken" appears to have retained no memory of their past life, but some connection to the Aether remained: Kasparov could detect residual Aether energies within their body, and more notably, the Taken could capture riftgates and repurpose them for human use, as well as open personal riftgates at will to transport themself and other humans. This became a critical factor in the resistance's successes that followed: captured riftgates were safer than other means of transportation, whether just due to overwhelming enemy presence or due to a need to take a path through the Void to bypass aetherfire-scorched land.

Faction Rewards
The Aetherial Nemesis is Valdaran, the Storm Scourge.