Katakros

Dude gave himself a bulge bigger than most heads.

"I take no joy in this. Nor do I despair. It is merely something that must be done. All we ask is payment of the Tithe. These people had their chance! They chose their fate! Perhaps I am wrong though... perhaps I deceive myself. For in truth, there is... some joy in this."

– Katakros on his 9 to 5.

"Wait till Biggus Dickus hears of this!"

– Pontius Pilate

"Every new beginning comes from some other beginning’s end."

– Semisonic Marcus Annaeus Seneca

Full name Orpheon Katakros, the newest member of the Mortarchs, Katakros had died and returned again and again, and had survived "The fall of the Storm God's hammer" meaning he had faced Sigmar Himself and was defeated. The other hints were that he died a general defending his birth city, and came back in death as an Emperor, and his promotional material was visually similar to Drachenfels, while some hopefuls thought that there was Tomb Kings influence in the army he led. This also came after the plot focused on Lady Olynder working to free an ancient evil that Sigmar had beef with in the past, with many people thinking that was either Drachenfels or Krell.

All of this could only mean one thing: he was a new character nobody had ever heard about before and is being included in an "oh by the way" fashion. If he had a voice, it would be Jim Parsons The Big Bang Theory (or for a serious example, Stephen Lang).

History

Hailing from the Realm of Beasts, in life he was an incredibly talented tactician and strategist, but not great at making friends due to being a self-centered perfectionist and workaholic. It also didn't help that in the army that he served, the vast majority of the upper command structure was made up aristocrats who had been appointed to their positions, and they did not take kindly to this bossy commoner upstart who had somehow risen all the way to become a general. He died for the first time against Beastmen when he made a charge but no one was there to support his autistic ass. As a result he got plucked off his chariot and ripped to pieces by a Ghorgon, (just managing to deal a fatal blow to it as he died).

Katakros' manner of death gave him a disdain for mounts of all kinds, so in undeath he walks everywhere. His soul first went to the afterlife Ossia, a place without a god where hard workers are rewarded by getting to do everything they enjoyed about their jobs with none of the downsides. Neighboring Ossia was another afterlife belonging to the same culture known as Necros, a place where the very same decadent aristocracy that had criticized and belittled Katakros' work lived out their afterlives being pampered and tended to as they had been in life. Seeing this disparity between Ossia and Necros, Katakros began harboring an ever growing resentment for his spoiled neighbors, feeling that they were unworthy of such a reward in comparison to all that he had done in his life. Katakros' skill saw him rise to the position of general, but no one liked him there either because he was as callous and single-minded as ever, which reminded them of Nagash. Speaking of the sociopathic skeleton, this was at the time Nagash had just started his omnoming of all the death gods and afterlives. Annexing Ossia's peaceful afterlife neighbor Necros, Katakros managed to defend his turf better than anyone else, to the point Nagash had to step in personally to curb stomp him. Katakros, seeing the situation was hopeless, offered his services before he was stomped out and Nagash actually said yes, which should say a lot about this boy.

He became the first Bonereaper, which was all fine and dandy until Sigmar invaded. Having been ordered to stop Sigmar by Nagash, Katakros took his forces to engage him despite thinking he could not actually win. After Sigmar smashed through his forces, Katakros, being "perhaps the greatest military strategist (living, or dead) the Mortal Realms have ever known" figured that he would be able to take Sigmar on in a one-on-one duel, guessing that that his glaive might be able to kill Sigmar because it was made using similar Warpstone methods to the weapon that slew Nagash in ages past. Naturally, Sigmar concaved the fucking idiot's skull with Ghal Maraz and won. Since this was before Sigmar thought about making the best warriors/leaders into Stormcast, (and apparently he didn't feel like turning "perhaps the greatest military strategist (living, or dead) the Mortal Realms have ever known" into a Sigmarine later), he threw the general into a Stormvault. Katakros spent his time mulling over tactics, stewing in his rage towards Sigmar and probably bouncing a ball against the opposite wall to pass the time. Unfortunately, rather than do something sensible like move it someplace Nagash couldn't easily access it, Sigmar trusted the enchantments to hide it from Nagash. Jump forward in time to the present, Lady Olynder opened it up and here he is, ready to start the Tithe.

Katakros back in the Age of Myth.

That being said, Katakros is the Mortarch of the Necropolis, and has his own legion, the Ossiarch Bonereapers (also called the Ossiarch legions). He also commands his own personal legion of 10,000 Bonereapers within the Ossiarch legions, and whenever one of his soldiers dies a new one is built back home and is then sent on a long journey to replace his destroyed soldier, making his army replenishment a logistical nightmare as it could take weeks to years to gain any reinforcements/replacements and a smart enemy could just attack them on the way, preventing them from ever reaching the main force. Unlike most undead characters inhabiting thin bone-bodies that are inevitably broken, Katakros is a soul housed within a fucking massive bone-construct (one that has a ridiculous bulge that would make David Bowie from Labyrinth blush) and also leads a legion of bone constructs, each housing several souls to make them more effective then brittle skeletons or slow-ass zombies (but for some reason still less effective than grave guard, who cost more than mortek guards for 10 points). Apparently Nagash saw Sigmar's Stormcasts and wanted to steal the gimmick for his own in revenge for all those tasty souls he will never own.

Katakros is also described as being "perhaps the greatest military strategist (living, or dead) the Mortal Realms have ever known", which is at odds with his track record seeing as how he fought and lost three times in three major ways. He is also seen as the paragon of Nagash’s dreams for the Mortal Realms; a consummate professional focused solely of the efficient completion of tasks, unfettered by the weight of emotion or free will despite demonstrating a capacity for joy and self-deluding in the above quote.

Also, he looks like a Primarch cosplaying as an Alien: Covenant Space Engineer. Because apparently THAT is a successful enough idea to rip off, even if it does match the alien molded bone look of his skeleton Stormcasts.

Currently Katakros is leading an invasion on the Allpoints, which means he was guaranteed to run into Archaon, the guy who beat both Sigmar and Nagash while Katakros beat neither. Unsurprisingly all of his bodyguards fall before Archaon, so he takes on the Everchosen himself and gets his ass kicked. Katakros even tries to play it off as a just as planned moment by possessing another body identical to his old one and claiming he meant to lose; apparently he has as many duplicate bodies as the plot demands (which makes you wonder why Nagash didn't make all of the Bonereapers like that). So now he's heading right back to the fight so that Archaon can rip him apart a second time.