- "Dread Emperor Tenebrous, I dredged up. He was the one to get it done. He’d seemed like a promising ruler early in his reign, until he’d made one deal too many with the Underworld and become convinced he was a giant spider stuck in a man’s body. Things had swiftly gone downhill after that."
- ―Book 1, Chapter 14: Villain
In his early reign he was a promising ruler. He oversaw the construction of an Imperial road from the Blessed Isle all the way to Ater. He also created a giant reservoir, to catch rain and freeze it, as an emergency water reserve for Ater when the city is in drought.
However, once he made too many deals with the Underworld he begun thinking he was a giant spider in a human body. It seems like he did actually turn himself into a giant spider, using either sorcery or devilry, as Ater’s sewers contain half a million of them, rumoured to be spawned from Tenebrous himself.
A rumour which was confirmed when a massive spider believed to be the progenitor of the infestation was unleashed from beneath Ater by Amadeus during the Battle of Spiders, with the High Lords all agreeing that it was Dread Emperor Tenebrous. Though there was some confusion on the address, as the giant progenitor spider was female.
The War College spends a fortnight teaching second year students about the spiders under the capital, as a demonstration of a victory that is not worth the effort. As such, instead of deploying troops to purge the infestation, the sewers are merely warded by district mages to prevent the spiders from reaching the surface. Still, there are the occasional spider that slips through and devours people nearby the sewers.
These spiders were later unleashed by Amadeus against Ater during the aptly named Battle of Spiders. He did so by killing the district mages responsible for warding the sewers, sending Ranger down to stir up the nest before letting the scent of battle draw them to the surface. All part of his plot in order to discredit the High Lords of the Wasteland by showing that the nobility preferred to use sorcery, devils and demons to fight and kill the spiders instead of sending their own soldiers and mages into battle. Causing indiscriminate destruction of entire chunks of the city as collateral damage.
Tenebrous herself was lured to the Licosian Gates by Ranger in order to fight the troops there. There, it fought in a melee between her own progeny, devils, Ranger, Ranger’s pupils (Archer, the Silver Huntress and the Concoctor) and the Emerald Swords, with some of the fighting even taking place on its back. Akua Sahelian also unleashed a great pillar of lightning using ritual magic against Tenebrous during this time, but she wasn’t able to either kill the massive spider or even force her into retreat.
Eventually, she was slain either by the Emerald Swords or Ranger, and subsequently raised as undead by Catherine, whom used her to force Ranger into retreat.
The threat of undead Tenebrous being unleashed against the Praesi nobility and their assets in Ater was enough to force Malicia into inviting the Grand Alliance into the Tower for her last session of the Imperial Court.
‘The paved street in front of them was ripped open, a massive leg tearing through it. Merciless Gods, Indrani thought. No, that couldn’t be. Wasn’t it supposed to be just a story? Another street blew up and slowly, inexorably, a gargantuan shape rose through the foundation of Ater. A spider so large and foul it defied description, shrouded in darkness and venom that dripped like rain. Her scream, when her hundred thousand eyes found the sun, was deafening. She was sniffing at the air, looking for a scent.
“Dread Emperor Tenebrous,” Indrani whispered.’
As a human, Dread Emperor Tenebrous was a Praesi human male.
In present times, Tenebrous is a female giant spider, with legs large enough to crush towers underfoot and loom over the high walls of Ater. Vivienne calls her ‘city-sized’. Her back is large enough to fight on, and is covered with hair.
Dread Emperor Tenebrous was noted to be a competent administrator and a promising ruler, commissioning many great public works for Praes, improving its infrastructure. Some of which, like the Imperial Road and a giant reservoir in Ater, still remain till this day.
He was mentioned to be a diabolist, though evidently not a particularly competent one, as he made one too many deals with the underworld, leading to his belief that he was a giant spider trapped in a human body. He (or his Warlock/mages) was also skilled enough in either sorcery or devilry to transform himself into a giant spider.
As a giant spider, Tenebrous is far larger than her progeny, being city-sized instead of horse-sized. As befitting her size, her legs can crush towers underfoot and trash entire sections of Ater by her lonesome. Her durability was also enhanced, withstanding Akua Sahelian’s giant pillar of lighting, a ritual which was powerful enough to incinerate lesser spiders instantly.
Besides that, Tenebrous is noted to have a good sense of smell, successfully tracking Ranger all the way from her nest in Ater’s foundations to the specific city district Ranger was at on the surface. Her other abilities include screeches which were powerful enough to shatter glass and outright kill some devils, poison, the ability to harden the hairs on her body to become sharp as iron needles as well as immortality or longevity enough to survive for centuries till present day.
Tenebrous can also spawn lesser spiders as her progeny, spawning an estimated half a million of them during her centuries beneath Ater. Each spider is mentioned to be the size of a horse, and subservient to Tenebrous.
Lastly, as testament to Tenebrous’ power, as a giant spider, she holds a domain. As stated by Archer:
‘Tenebrous scattering the stone walls like they were made of parchment and dripping darkness everywhere. Like pools of ink the dark tainted whatever it touched, spreading down slopes and through crevices. Twice now Indrani had seen devils fall through a large patch as if it were a hole. Cocky had said that Tenebrous was living domain, but Archer had her doubts. Althea Maronid’s research in Ashur had decisively proved that a domain must be internal if it belonged to a living creature, else it would cause uncontrolled creational cascades.
More likely Tenebrous’ domain was physically incarnated and static, somewhere far below Ater, and she was trying to bring it up here by spreading around that darkness clinging to her hide. On the bright side, that meant climbing on top of the spider wouldn’t be like stepping over one of the pools: if the domain was external it wouldn’t work on the creature herself.’
This domain manifests itself as darkness that Tenebrous can spread around. The darkness can change in constitution from misty to mud-like. Large patches of it were enough to swallow devils up.