Fulminiss was a male Human Sith Lord who was regarded as one of the most powerful Sith sorcerers in the reconstituted Sith Empire. A master of the dark side's more arcane and lethal aspects, Fulminiss served the Sith Emperor as one of the Empire's foremost masters in Sith alchemy and magic, and excelled in eliminating the populations of entire planets. In the early days of the Galactic War with the Galactic Republic, the Emperor sent Lord Fulminiss to the planet Voss in order to start his life-consuming ritual by causing millions of simultaneous deaths, and the Sith sorcerer enlisted the aid of the Voss Mystic Valen-Da in his efforts to use a corrupted healing ritual to drive the planet's inhabitants into murderous insanity. However, Fulminiss was betrayed by Valen-Da, who arranged for the Voss commando Tala-Reh and the Jedi Knight known as the Hero of Tython to interrupt Fulminiss's efforts to conduct the ritual with the aid of the dark side entity Sel-Makor, and Fulminiss was killed in battle with the Jedi and the Voss.
A male Human, Fulminiss was a Sith Lord of the Sith Empire who quickly became regarded as one of the greatest Sith sorcerers throughout the Empire. During his career before and during the Great Galactic War with the Galactic Republic, Fulminiss became an expert on mass extermination through Sith magic, and the Sith Emperor himself requested Fulminiss perform extensive research into eliminating the populations of entire planets. He also conducted extensive experimentation and research in Sith alchemy, creating the grotesque Harrower assassins that guarded the Emperor's Fortress, and one of the Sith Lord's most legendary accomplishments was the disintegration of an entire city of rebellious natives on the conquered planet of Jabiim with a raging storm of pure Force energy.
Fulminiss's crowning achievement was the creation of the Seeds of Rage, subterranean machines that utilized a combination of low-frequency transmissions and pure dark side energy to subtly manipulate the emotions and thoughts of all nearby living creatures. The Seeds drove their victims homicidally insane over time, contaminating them with dark side energy and causing corrupted dark growths to form on both the bodies of their victims and the surrounding environment. The Seeds were stored in the Arcanum, the Emperor's personal storehouse of Sith artifacts, when they were deemed too powerful to be used frequently. The Emperor's Wrath Lord Scourge, the Emperor's personal enforcer, knew of Fulminiss's capabilities, and the Sith Lord Darth Acina considered Fulminiss to be one of the most gifted alchemists of the Empire.
Around 3640 BBY, during the Galactic War between the Empire and the Republic, Fulminiss was dispatched by the Emperor himself to the planet Voss, where Fulminiss was ordered to use his knowledge and expertise to bring about millions of simultaneous deaths among the native Voss and Gormak species. With a number of Sith apprentices, Fulminiss established a base in the Old Paths region of the world. While preparing for to test rituals of Sith magic on Voss subjects, Fulminiss was approached by the Voss Mystic Valen-Da, who had foreseen that Fulminiss would, with the help of the dark side entity known as Sel-Makor, try to destroy all of Voss; but Valen-Da had also foreseen the means to stop Fulminiss and Sel-Makor, so the Force-sensitive Mystic joined Fulminiss and offered to grant him access to the Voss Shrine of Healing so that he could learn a Voss healing ritual that could heal damaged bodies and minds. The two returned to Fulminiss's base, where Fulminiss tested his abilities on the apprentices and drove them insane, eliminating the loose end they posed in the process.
The two then traveled to the Shrine of Healing, where Fulminiss learned the healing ritual from the spirits of the long-dead Mystics Laeras-Wu, Shanatka-Lo, and Hanar-Ye, but the Sith Lord corrupted the ritual so that it would tear apart the minds of its victims and drive them insane. With the power of the ritual, Fulminiss was then able to affect many more victims from a greater distance than before, but it was not enough to complete his mission, and he departed the Shrine with Valen-Da at his side. By that time, Fulminiss had become aware of the existence of Sel-Makor, which was a powerful dark side entity that was located at the center of the region known as the Nightmare Lands. Over three days after they had departed the Shrine, Fulminiss and Valen-Da arrived at the Dark Heart, the seat of Sel-Makor's power, and Fulminiss conversed with Sel-Makor and explained his plans. Sel-Makor was more than willing to aid in the destruction of the Voss and the Gormak and agreed to lend Fulminiss its power, and Fulminiss began his preparations.
However, Fulminiss was surprised by the arrival of the Hero of Tython, the Jedi Knight who had escaped from the Emperor's thrall recently and was working to halt the Emperor's agents, one of the Jedi's companions, and the Voss commando Tala-Reh, all of whom had been following Valen-Da's trail. Enraged by Valen-Da's betrayal, as the Mystic had left a message to Tala-Reh to lead his pursuers to the Dark Heart, Fulminiss drew his lightsaber and attacked the intruders, his strength bolstered by Sel-Makor. Fulminiss's enhanced strength ultimately was not enough to overcome his three opponents, and the Sith Lord fell in battle, his mission for the Emperor unfinished. His death and the loss of his expertise in the dark side was mourned by a number of Sith Lords, including Darth Acina.
Fulminiss was a powerful Force-sensitive Human with red eyes, cybernetic implants underneath his eyes, and a skin that had a sickly grey pallor. He wore gray and red hooded robes with black and purple markings, and Fulminiss was a cruel individual who took pleasure in dealing death on a massive scale. The Sith Lord was considered an enigmatic genius by many of his contemporaries, and he was more than willing to put his knowledge and talents to use in the extermination of entire species without any regret or objections. Fulminiss paid little attention to Valen-Da during his mission to Voss, allowing the Mystic to leave clues and messages for Tala-Reh and the Hero of Tython so that they could pursue the Sith Lord.
A greatly respected Sith sorcerer with decades of experience, Fulminiss was a master of both Sith magic and alchemy. His knowledge of the dark side and the fields of Sith magic and alchemy in particular were unrivaled; the Emperor himself requested Fulminiss's talents more than once, and members of the Empire's ruling Dark Council often paid great sums to acquire Fulminiss's research notes and reports of his work for their own studies. In battle, Fulminiss wielded a purple lightsaber, and he used the Force to overwhelm his opponents with nightmares and fear. A highly skilled Sith sorcerer, Fulminiss also experimented in merging technology with Sith alchemy, using the resultant combinations to drive creatures and beings insane or altering their physical form, and he considered the Harrower assassins to be his favorite creation. Fulminiss was also capable of summoning storms of pure Force energy; such storms could annihilate entire cities with their destructive power.
Fulminiss was first introduced in the 2011 BioWare video game Star Wars: The Old Republic, where he is a primary antagonist in the Jedi Knight class storyline on Voss. It is never made entirely clear how Fulminiss becomes aware of Sel-Makor; the Emperor encountered Sel-Makor shortly before sending Fulminiss to Voss, but it is not explained whether Fulminiss learned about the entity from the Emperor, Valen-Da, or another source. Fulminiss is also mentioned in Rise of the Hutt Cartel, the 2013 Digital Expansion to The Old Republic, as the creator of the Seeds of Rage. Fulminiss's death is also mentioned by the Sith Lord Darth Acina, and the Seeds are the subject of the seeker droid missions for both the Republic and the Empire.