Darth Vehendal was a male Quarren Dark Lord of the Sith and a member of the Initiates of Dxun. Originally named Swirro Nent and the son of a wealthy businessman from Dac, the young Force-sensitive who would become Vehendal was kidnapped by pirates while en route with his father on a business trip to the galactic capital of Coruscant. While it was first assumed that the pirates planned to ransom him to his family members on Dac, it soon became apparent that the Quarren heir had either been murdered or long lost and the search for him eventually ceased.
In truth, he was kidnapped by a group of deranged Sith fanatics who had been mentally corrupted and manipulated through the Force by the mysterious Sith Force-ghost called Tvath, and was brought to the Demon Moon to receive training in the Dark Side.

After many years as the Tvath's favorite, Darth Vehendal was recruited into the Sith Ascendancy. A long war of domination ensued, which saw many of Vehendal's fellow Initiates killed after the return of the Jedi Order from exile on Illum. With the Jedi assisting Mandalore the Inexorable and the Tair Republic in pushing back the Ascendancy, Darth Vehendal found himself alone at the head of the wounded animal, banished ever further beyond the galactic Outer Rim Territories with each succeeding battle. It was a war he could not win. The fallen Sith empire would remain, weakened but intact, until after his death in 331 ABY.