As a male Human Sith Lord belonging to the Sith Empire, Darth Vengean held the position of Sith Master to Darth Baras and served as a member of the Dark Council. Occupying the role of military leader within the Dark Council, he fervently advocated for the resumption of hostilities with the Republic, aiming to ultimately eradicate the enemy that had forced the Sith into exile a millennium prior. Vengean voiced his open disapproval upon the enactment of the Treaty of Coruscant, criticizing those who supported the peace agreement and even subtly denigrating the Sith Emperor. The fact that he survived such disrespect was a demonstration of his considerable strength. Vengean, alongside Baras, dedicated years to executing skillful political maneuvers and covert assassinations, targeting both the Republic and elements within the Empire itself.
During the period known as the Cold War, Vengean initiated schemes to reignite the galactic conflict. He assigned Baras the task of eliminating General Karastace Gonn, whose actions were impeding the Empire's progress in conquering the outer systems. Baras deployed his newest apprentice, a formidable Sith Warrior, to accomplish this objective. This allowed Vengean to deploy his flagship to begin his conquest. However, Republic Admiral Monk, who was revealed to be a spy for Baras, was lying in wait and ambushed the flagship, thereby damaging Vengean's reputation and nullifying the Treaty of Coruscant.
Upon the completion of Plan Zero, Baras summoned the Warrior back to Dromund Kaas to deliberate on Vengean's impending downfall. As a result of his misstep on Quesh, the Dark Council demanded Vengean's execution. Baras dispatched the Warrior into Vengean's sanctum with the intention of freeing Lord Draahg, Vengean's apprentice who was secretly in league with Baras. However, Vengean discovered the plot before the Warrior could rescue Draahg and imprisoned him. After Draahg was freed, the two collaborated to infiltrate Vengean's inner sanctum, where the Dark Lord was amassing his power. Confronted by his adversaries, Vengean vowed to inflict further suffering upon Draahg before turning his attention to the Warrior. He reminded the young Sith that Baras's success was contingent upon the assistance of a strong enforcer. He denounced Baras as a coward, operating from the shadows, while both the Warrior and Vengean himself were individuals of action. Vengean then engaged in a duel with Baras's apprentice, ultimately succumbing to defeat, which enabled Baras to assume Vengean's position on the Dark Council.
Darth Vengean's physical characteristics included pale skin and orange eyes, marking him as a Human male. Vengean's reputation was that of a warmonger, a man known for taking action. He harbored intense animosity towards those who betrayed him, evident in his threats to inflict pain upon Draahg and destroy Baras for their treachery.
Darth Vengean demonstrated proficiency in wielding a single-bladed Sith lightsaber. Furthermore, Vengean possessed considerable power in the dark side of the Force and exhibited capabilities in Force choke and telekinesis.