Thaszar, or Thaszar the Invincible as he prefers to be known, is a Necron Overlord who has become a self-styled Necron pirate king originally of the Sarnekh Dynasty. Exiled from his Tomb World of Zapennec during the War in Heaven to what would eventually become the Imperial colony world of Athonos, he has since awoken in the late 41st Millennium and now leads raids across his region of space after retaking control of Zapennec for himself and naming himself the Phaeron of the Sarnekh Dynasty.
In 824.M41, the shadow-shrouded Imperial world of Athonos was wracked by severe earth tremors. The cause remained a mystery to the planet’s populace until a colossal Cairn-class Tomb Ship, captained by the Necron pirate king Thaszar the Invincible, emerged from beneath the ground; shedding soil, rock and fragments of hab-block from its hull as it rose after sixty million standard years of hibernation. The world's defences were, understandably, in disarray due to the event, but fortunately for Athonos’ inhabitants, Thaszar had yet to realise that humans are an intelligent form of life, and payed no more attention to the panicked defenders than he would to a nest of insects. Whilst the Athonosian planetary capital lay in ruins, the rest of the planet survived relatively unscathed as the Tomb Ship headed into the stars, towards the Tomb World of Zapennec, the Crownworld of the Sarnekh Dynasty Thaszar had been exiled from, pausing only to obliterate a holo-stealthed Eldar listening post hidden in near-orbit for long millennia.
Upon reaching Zapennec after being driven by an urge he could not identify, Thaszar found its people deep in hibernation. Taking advantage of this opportunity, he inveigled his way into the Tomb World's master program. In short order he convinced the master program that he, Thaszar the Invincible, was no dishonoured Necron noble returned from exile, but in fact the rightful Phaeron of the Sarnekh Dynasty! For good measure, he then ordered that his updated status be engrammatically encoded into the minds of the Tomb World's slumbering Necrons. So did the most notorious outcast of Zapennec become its ruler, and those who had banished him become his servants. Under Thaszar's command, the ancient and noble crownworld of the Sarnekh Dynasty has been made over into the Reaveworld. In the shroud of orbital wreckage surrounding the planet dating back to the War in Heaven, Thaszar has access to all the raw materials he will ever need to build a Necron pirate fleet the scale of which has not been seen for 60 million standard years; in the reprogrammed Necrons of Zapennec, he has crews and captains of unfailing loyalty. Thaszar's vessels have already begun to prowl both the Webway and realspace, and the galaxy will surely come to rue the day he awakened
- Codex: Necrons (5th Edition), pp. 16, 25