Skulltaker is the greatest of Khorne's bloodletters, though like Ku'gath Plaguefather, his personality differs greatly between 40k and Fantasy.
40k: The Ragemonster
The moment Khorne created him was also the day he scored his first kill by slaying the first creature he met via chopping off its head. That creature was another Bloodletter.
After scoring his 888th skull for the Skull Throne, Khorne promoted U'Zhul to the rank of Sacred Executioner, and thus he earned his moniker of Skulltaker, swelling in size, and his blade growing in power.
Skulltaker is extremely competent and dead serious when it comes to fighting (and that's saying something about him, as Bloodletters treat war and slaughter as serious business). When the fighting is extreme, and the slaughter is immense, he will walk the battlefield looking for exceptionally powerful warriors and challenge them to manly combat one on one. Those who flee are immediately murdered, and those who stand their ground are murdered at a much slower rate, as Skulltaker likes to toy with his prey like a cat before killing it. Skulltaker is a master duellist beyond and above the capabilities any other Bloodletter could possibly achieve. The daemon cuts off his adversary's limbs, and when they're reduced to a helpless, limbless mass, grabs their heads and utters the eight Words of Sacrifice. This wreaths his victim's head in magical flames that burn away their flesh; sparing only a bare skull that he throws into a sack he carries, along with the other skulls he collected while fighting. He'll often lift said skulls up in the air for everyone to see them.
After a battle, he returns to Khorne's Brass Citadel to give the skulls he collected as offering to the Blood God. Most of them Khorne collects, but the skulls of the most exceptional of opponents he lets Skulltaker keep as personal trophies that he sews into his cloak.
The Bloodletter's achievements are as follows:
- Slaying a quarter of the Grey Knight Brother Captains during the First War for Armageddon. Even though this only adds up to two, this is still enough to seal his status as total badass since he's a daemon that killed two experts at daemon-slaying.
- Slaying the Ork Warboss Grimsnag Urk and his Mega Armoured Nobz on Agripina-6.
- Slaying 17 Eldar Exarchs on Haranshemash (seems they gravely underestimated him).
- Dueled Castellan Crowe for SEVERAL HOURS (keep in mind that the Grey Knight
cheatedevened the handicap by throwing super-special holy water at Skulltaker before the duel).
Warhammer Fantasy: The Honourable Warrior
Skulltaker in Warhammer Fantasy is strikingly different than his 40k counterpart in one very notable way: you make him go away by ignoring him. Seriously.
In Warhammer Fantasy, when he is not campaigning, Skulltaker roams about on the back of Kuhl'tyran, his Juggernaut, and seeks out mighty fortresses and strongholds, either in the Realm of Chaos or in the mortal plane. When he finds one, he calls out those inside, throwing challenge after challenge until one of them get fed up with the jackass (presumably for not letting them sleep) and leaves to shut him up. This is always a terrible idea; Skulltaker knows every possible weakness of their opponent, and after saluting them for being brave enough to challenge him (and dismounting from his Juggernaut so that it will be a fair fight), he will break/cleave their limbs, before gripping their skull, burning their flesh off with magical flames that emerge from his fingertips, before ripping the clean bone away from their corpse with a single practiced twist.
Once he fells his initial opponent and throws their skull into his trophy sack, Skulltaker resumes challenging those who remain, striking down any further challengers, until there's either nobody left, or he grows bored, after which Skulltaker leaves.
This makes Skulltaker one of the easiest Daemons to deal with, as despite being the greatest of Khorne's Bloodletters, Skulltaker actually cares about consent, weirdly enough. He wants a challenge; tales of martial prowess and rumour of mighty combatants draw him towards anybody who might give him some kind of fight, and he will not fight anyone who refuses to accept his duel to the death. There's nothing to lose but ego (and possibly sleep assuming he yells loudly enough) if you ignore him, so if you put up with the annoyance, he'll leave eventually.
The only time Skulltaker is ever recorded as having lost is when he challenged Sigmar himself in the World's Edge Mountains. Supposedly the duel lasted for three days without pause, but ultimately Sigmar stood triumphant, banishing the daemon and leaving him a permanent scar. Because of this, Skulltaker takes great pleasure in targeting challengers from the Empire specifically, after all, he has a very long memory and little desire to grant forgiveness.
Skulltaker's cloak in Warhammer Fantasy also has a special function besides ego: with every skull added to it, he inherits a portion of his enemy's strength. Because of this, he only keeps the skulls of mighty opponents, ones who could give him a satisfactory fight or a close call, and all others he gives to Khorne. These skulls he truly cherishes, and he's always looking for more to add to his cloak.