A thought bomb was an outcome from an ancient ritual that, through the combined and concentrated will of numerous Sith Lords, unleashed the complete instability of the dark side of the Force. Upon its activation, this destructive device completely eradicated all Force-sensitive beings within its area of effect, encompassing both their physical and spiritual forms. The fragmented souls of these beings were then drawn into a perpetually agonizing vortex, ultimately coalescing into a shimmering orb of silver. The ancient Sith first developed the capability to wield such immense destructive force. However, the thought bomb's roots can be traced back to the Ritual of Nathema, where the Sith Lord Vitiate consumed an entire world. The details of the thought bomb were later uncovered during the Jedi Civil War by the Dark Lord of the Sith Darth Revan, who documented its creation secrets within his Sith holocron. This Revan's holocron and the contained thought bomb ritual remained concealed within a forgotten temple on the planet Lehon. It stayed hidden until its discovery in 1000 BBY by the Sith'ari, Darth Bane. Bane then shared the creation instructions with Lord Kaan, the leader of the Brotherhood of Darkness, as part of his scheme to dismantle the Brotherhood and re-establish the Sith under his new order. However, Bane misled Kaan, leading him to believe that the Brotherhood would endure the bomb's effects. In a desperate measure to conclude their ongoing war with the Jedi, Kaan's Sith Brotherhood fabricated and detonated a thought bomb. This action annihilated almost all sentient Force-sensitive life on the planet Ruusan. Over a millennium later, the spirits of the defeated Jedi, trapped within the thought bomb, were liberated through the bravery of Kyle Katarn, a young Rebel agent and Jedi Knight.
Constructing a thought bomb necessitated the concentrated focus of multiple Sith Lord participants, each possessing significant strength in the dark side of the Force. Gathered in a circle, linked by their hands, the individuals would begin chanting an incantation. This chant rapidly drew upon the Force, funneling it into the center of their formation. As the expanding darkness swirled within the circle, the minds of the united Sith merged into a singular consciousness, enabling them to shape the harnessed energy. As the ritual progressed, the thoughts, awareness, and identities of those involved were consumed by the vortex. This process stripped them of their individuality, transforming them into a single entity within the Force. Forgoing any further physical contact, the participants would raise their hands toward the center, giving material form to what was previously immaterial: the recited incantation that linked their collective will with the power of the dark side. The summoned power became so concentrated that it warped the very fabric of reality within the circle. The breath of those gathered became visible as the ambient temperature plummeted, causing frost to accumulate on their extremities and the surrounding area's tapered protrusions. All light, heat, and sound were drawn into the thought bomb's vacuum. Tendrils of energy from a cloud of absolute darkness formed above the ceremony's master, who had by then positioned himself in the center of his companions.
The initial stage in constructing the bomb involved creating its mental "shell," within which the dark side users would then channel dark energy.
A simple clap of hands would instantly trigger the thought bomb, transforming the essences of those affected into an oblong sphere. This sphere absorbed all light but emitted a faint radiance of its own, pulsating with rhythmic vibrations. The dull gray, flat, and slightly iridescent orb shimmered with the smoke-like shadows of its trapped victims. Despite its often grotesque and repulsive nature, living beings in its vicinity were compelled to gaze upon the thought bomb's final form. It floated approximately a meter above the ground, measured four meters from top to bottom, and had a circumference of about three meters. This ovoid, similar in size and shape to another ancient Sith weapon, burned with a cold fire upon contact. The shadows within converged on the point of contact, whispering suggestions of hate and despair to anyone curious enough to touch it.
The thought bomb, a weapon notoriously difficult to control, exposed its creators and those nearby to a multitude of potentially fatal dangers. Attempting the ritual was widely regarded as an act of suicide. During the creation of Kaan's bomb on Ruusan, three of his Dark Jedi perished, while others descended into madness. The Sith Master-at-arms was forced to execute those who became uncontrollably violent.
Individuals particularly strong in the dark side retained only a vague awareness of their senses, both tactile and otherwise. Most participants, however, remained completely captivated and unable to resist. The initiators, positioned closest to the detonation point, suffered the same fate as those targeted by the bomb. The deafening explosion obliterated everything in its path, and the souls of all Force-sensitive beings in close proximity were torn apart as they were drawn into the bomb's epicenter, destined for an eternity of unending torment. Those who survived the initial detonation were not immune to its lingering effects. Some experienced persistent headaches and even hallucinations in the hours, days, and weeks following the detonation. Mentally penetrating the orb meant subjecting oneself to the agony of the shattered souls imprisoned within, an eternal madness endured by the spirits of what were once sentient individuals. The tormented souls would assault the intruder en masse, attempting to drag them into the inescapable depths of their suffering. The aftermath of a successful thought bomb also resulted in a powerful Force nexus, causing abrupt shifts in weather patterns on the planet where it was detonated. Consequently, indigenous animals unable to adapt to these changes faced extinction.
The ancient Sith designed the thought bomb to eliminate all Force-sensitive opposition, primarily Jedi, but it was reserved as a last resort when no other means of securing victory existed. The willingness to employ such devastation was often attributed to the creators' madness, given their apparent disregard for their own potential demise. Indeed, when detonated, a thought bomb indiscriminately killed every Force adept in its vicinity. However, immense strength in the Force or maintaining a significant distance from ground zero increased one's chances of survival.
History attributes the knowledge and usage of the thought bomb to the ancient Sith. However, the thought bomb's origins lie in a ritual of Sith magic employed by the ancient Sith Lord Vitiate. This ritual involved Vitiate binding the strength of thousands of fellow Sith Lords and using it to consume all life on his homeworld of Medriaas, granting him immortality. A millennium later, Darth Revan, the Dark Lord of the Sith and instigator of the Jedi Civil War, recorded a transcription of his knowledge of the ritual within his personal holocron. Revan's holocron remained well-hidden in the Rakatan Temple of the Ancients on the world of Lehon for nearly another three thousand years, until Darth Bane, the prophesied Sith'ari of ancient Sith legend, found and studied it in detail. By that time, stories circulated among students in the Jedi Temple about the destruction caused by a thought bomb.
Newly bestowed with the title of Dark Lord, Darth Bane discovered Revan's holocron and learned of Vitiate's ritual. He used the transcription as inspiration for the actual thought bomb, intending to use it as a means to highlight his new philosophy, the Sith Rule of Two. Bane traveled to the planet Ruusan and shared the details of the thought bomb's implementation with Lord Kaan, the leader of the Brotherhood of Darkness, whom Bane believed was leading the Sith to their doom. Bane's primary goal was the complete eradication of the Brotherhood, and he knew that Kaan's unwavering desire to win the latest campaign in the protracted war against the Jedi and Galactic Republic would motivate him to use the thought bomb. Just before the final battle of Ruusan, Bane manipulated Kaan into using a thought bomb to destroy the Army of Light, intentionally deceiving him into believing that the Brotherhood would survive the effects. During the final battle of Ruusan, all the Dark Lords joined Kaan in an underground bunker. As the Jedi's Army of Light surrounded the area, the Sith began performing the thought bomb ritual. Led by Jedi Lord Hoth, 100 Knights pursued Kaan the following morning and confronted the Brotherhood within the cave, attempting to prevent their reckless use of power. However, they were too late; the thought bomb had already been created. As Hoth rushed Kaan, the Dark Lord detonated his weapon, instantly vanquishing him, the entire Sith Brotherhood, and all 100 Jedi who were in the cave, consuming their spirits in the seething vacuum.
Having tricked the Brotherhood into destruction, Bane emerged as the sole survivor and encountered a young girl named Zannah, whom he made his apprentice under his Rule of Two. While they were the only Sith survivors, and although both felt the wave of dark side energy pass over them, they were distant enough to only feel the reverberations of the blast. Later, they traveled to ground zero, where Bane examined the metallic globe formed from the detonation and was satisfied with the outcome. The thought bomb's pall attracted others, including a young Human boy named Darovit, and many of Ruusan's native Force-sensitive Bouncers. Bane realized the residual effects in the days and weeks that followed, manifesting as terrible headaches and vivid hallucinations of deceased Brotherhood members, which eventually subsided. The Jedi feared the thought bomb's aftereffects and ordered an immediate evacuation of all Force-sensitives on Ruusan. Almost overnight, the planet transformed into a desert wasteland, and many of the Ruusanian natives and off-world colonists perished in the explosion. The irreparable damage to Ruusan's biosphere caused by the thought bomb introduced the annual phenomenon of snow in subsequent years, a change that led to the extinction of many of the planet's domestic fauna. The release of such potent energy, combined with the broken spirits trapped within the bomb's void, turned the zero point into a Force nexus, equally balanced between the light and dark sides of the Force. In remembrance of the Jedi's valor, the Republic commissioned the creation of the Valley of the Jedi monument on Ruusan to commemorate the sacrifice made by the victims of the thought bomb. The Masters of the Order recounted the story for centuries.
The Ruusanian survivors of the thought bomb remained on their homeworld, enduring a life of hardship due to the devastated planetary ecosystem. The Republic abandoned Ruusan in the years that followed, and the planet, along with the Force nexus that was the Valley of the Jedi, were forgotten, their locations nearly lost due to shifting nearby nebulae. For the next thousand years, the Jedi spirits endured perpetual torment within their prison. In 5 ABY, Kyle Katarn, a Force-sensitive Rebel Alliance operative, learned of the Valley's coordinates and wrested control of the nexus from Jerec, a megalomaniacal Dark Jedi. This confrontation resulted in Jerec's death and the release of those imprisoned within the remnants of the only known thought bomb ever created.
The thought bomb made its debut in the October 1998 novella Dark Forces: Jedi Knight, the final installment of author William C. Dietz's Dark Forces trilogy, where protagonist Kyle Katarn experiences a Force vision of the last battle of Ruusan. The same event, portrayed with slight differences but still featuring the thought bomb, was fully explored in the 2001 release of Darko Macan's Jedi vs. Sith comic series. Minor inconsistencies exist between Jedi vs. Sith and the weapon's subsequent appearance in Drew Karpyshyn's Darth Bane Trilogy of novels, starting with Path of Destruction, regarding the thought bomb's creation and the circumstances of its release. The thought bomb later appeared in the second Darth Bane novel, Rule of Two, and was mentioned in the third, Dynasty of Evil. The thought bomb also received mention in Kevin J. Anderson's Bane of the Sith and Ryder Windham's The Life and Legend of Obi-Wan Kenobi. The Star Wars: Force and Destiny Core Rulebook slightly alters the bomb's origin, attributing it to Revan's memories of the planet Nathema.
While Jedi vs. Sith and Path of Destruction present relatively similar accounts of the same event, there are minor distinctions. Jedi vs. Sith depicts Kaan seated on a throne when confronted by the Jedi, while Path of Destruction portrays the Jedi charging into the Sith perimeter surrounding a standing Kaan as he prepares the thought bomb for detonation. Furthermore, both sources differ considerably from Dark Forces: Jedi Knight, which specifies a greater number of Sith participants and Jedi victims, variations in the ritual's performance, a different description of the thought bomb's appearance, and a different ground zero. The rendition depicted in Jedi vs. Sith and Path of Destruction is supported by subsequent Star Wars source and guidebook material, including Star Wars: The Ultimate Visual Guide, The New Essential Chronology, Jedi vs. Sith: The Essential Guide to the Force, The Complete Star Wars Encyclopedia, and The Essential Atlas.