The Soulsaber was a dark-side weapon that was similar in design to a lightsaber. The Soulsaber's forty-five-centimeter-long hilt consisted of a deep black cylindrical rod wrapped in a bronze-like metal that was formed into the shape of a dragon. When the weapon was activated, a one-and-a-half-meter blade of energy was emitted from the open jaws of the dragon. The blade took on a deep violet hue and consisted of an obsidian-colored core with blood-red flecks flashing up and down the blade's length.
More of a manifestation of the dark side of the Force itself than simply a weapon of the dark side, the Soulsaber was an abomination to the light side and all life. It was a nexus of dark-side energy, and its presence could be felt by anyone standing within ten meters of it. Non-Force-sensitive beings felt very uneasy in its presence, while Force-sensitive beings experienced great discomfort in the form of headaches or nausea, finding it difficult to concentrate on a particular task, and were aware that they were near a major source of dark-side energy. Any being untainted by the dark side who touched the Soulsaber was immediately hit with a backlash of dark-side energy.
The Soulsaber was created not only to destroy life, but to corrupt Force-sensitive beings to the dark side. Simply igniting the weapon filled the wielder with negative emotions, such as anger, aggression, and fear, and the wielder heard a dark whisper of great power inside their head. This alone could turn some beings to the dark side and had the potential to create infighting among a group of darksiders who each wished to possess the weapon. While the Soulsaber's energy blade acted much like a lightsaber's, any being struck by it felt a stab of unbelievable and agonizing cold, and was flooded with emotions intended to push them over the brink to the dark side. The wielder, too, was pushed further to the dark side each time they struck an opponent.
In combat, the Soulsaber provided its wielder with the Force ability Battlemind, giving them greater prowess in battle through enhanced concentration and commitment. The wielder's stamina was augmented so that they could continue fighting even at the brink of death, but at the price of never knowing how close they were to dying at any point. The Soulsaber could also siphon Force energy from any being it struck and temporarily channel it to the wielder; energy could also be drawn from the wielder's surroundings.
The Soulsaber was built by a Dark Jedi, and he used it in a bloody battle on Pamorjal against the Jedi Order, in which many Jedi Masters died. However, the Dark Jedi was ultimately defeated, and the Jedi concealed the Soulsaber in a remote system, protecting it with the light side of the Force in the Cavern of Light on the planet ZXK-100346.6a. The Dark Jedi Thaum Rystra later went and stole the artifact with the unwilling assistance of Caeleb, who enabled Rystra to bypass the light-side protection.