Arch-Kavalos Zandtos
Arch-Kavalos Zandtos is a Liege-Kavalos of the Mortis Praetorians Legion, serving as Katakros' top lieutenant. He is one of the very rare few Bonereapers (alongside Katakros and maybe Vokmortion) that's made using only one original soul. His steed also looks more draconic compared to the more amalgamated equine-porcine look other Kavalos steeds have, and at the meta level is a popular choice for conversions.
History
Origins
In life, Zandtos was a refined assassin with an autistic fixation on death, and like Katakros, he was also from Flezich in Ghur. Zandtos spent most of his life as an assassin-mortician. For over sixty years, he was sent after targets, riding by himself to meet them before dismounting and dueling them. Zandtos is also skilled fighter, to the point that he strived to make the deathblow as careful and clean as possible, to the point of inflicting it with almost loving care. Unlike other assassins, he also cleaned and interred his victims, even though that meant digging a grave for them and sometimes even scooping up their organs and severed body parts.
When Zandtos died, like many Flezichans, he went to the underworld of Ossia. Given Ossia revolved around hard work being its own reward, this was Zandtos' idea of paradise, and he enjoyed tending to the dead and undead alike. Then one day Sigmar came along and brought living people to Shyish. They were loud and passionate, killing their enemies with great violence and leaving their corpses messy. This enraged Zandtos, every time he saw this angering him more until he reached the tipping point, where he began a one-man campaign of genocide against any living beings in Shyish.
At an unidentified point in time after Katakros arrived in Ossia, Zandtos approached Katakros and offered his services, seeing Katakros as someone who could help fulfill his genocidal ambitions. Eventually, Zandtos rose to the rank of Katakros' general.
Age of Chaos
In the Age of Chaos Zandtos fought alongside Katakros, and was present when Katakros annexed Necris under the rule of Ossia.
Age of Sigmar
Zandtos joined Katakros after he was freed from the Stormvault, and helped him reclaim Ossia and Necris from the forces of Chaos. He was also gifted with the weapon The Dark Lance, a lethal blade that increase the force of its wielder's blows and focuses their intent. In the case of Zandtos, it intensified his desire for death above all to the point he lost his desire to bring order and tidiness to the underworld. Since the coming of the necroquake, Zandtos forsook the mortician's code of dignity and repose in death and now in battle he leaves behind the disorder and carnage he once despised.
He was present in the War of the Eightpoints, leading Katakros' armies across the land to fight and hunt the forces of Chaos. He led a charge against the Varanguad when Archaon himself returned. Archaon sent Dorghar to attack the Deathriders and he smashed many, including Zandtos to splinters.
Fortunately for Zandtos his soultrap gem, weapons and badges of officer were retrieved by his retainers, who implemented a tactical retreat so he could be restored, all in accordance with Katakros' plan.