"Nice, you're getting a lot better at this." Sukuna said, grinning as Horus channeled RCT and regrew his right arm, which Sukuna had earlier taken with Cleave. All part of their very friendly spar, since Magnus was taking his sweet time and none of them had anything better to do. So, seeing as they were literally built for war and death, many of the Primarchs, including Sukuna himself, decided that it was a good idea to start sparring.

Horus grinned back and stretched his newly regenerated right arm. "It has been many years since we last met, brother. I've had plenty of practice."

"That's good to hear," Sukuna replied. "That means I get to stop holding back."

Usually, he'd never make use of his Cursed Technique in a spar, except maybe against Vulkan, but Horus asked for it and assured him that he'd be fine. So, Sukuna obliged. One Cleave and Horus' right arm went flying. The Khan, who'd been watching the spar from the sides, alongside Lorgar, Corvus, and Vulkan, raised a curious brow. None of them appeared truly surprised, however, and it was likely that they'd seen far worse. Horus, after all, loved to work with other Primarchs on his campaigns and likely showed off his newly-acquired RCT.

Unfortunately for Horus, his Cursed Technique was not entirely useful for personal combat. It was amazing on the battlefield, similar to Sukuna's Inspire ability, but not much of use outside it. Blood Command, Horus called it, the ability to take full control over any creature that ingests even a single drop of his blood. And Horus hadn't even begun to explore the depths of its potency. If Sukuna was right – and he usually was – about its full potential, then Horus could use this ability to reincarnate within the body of whoever ingested his blood, becoming them. Of course, Horus likely never even conceived this possibility, because the very idea of doing so would've been abhorrent. Instead, he used it in a manner that mimicked Sukuna's Inspire, channeling RCT through the blood connection to heal the Luna Wolves who couldn't heal themselves.

Another interesting thing that was, while a few dozen Luna Wolves developed their own jujutsu, most of them simply did not. How or why that was the case, Sukuna did not know – or care, honestly. But it was mildly interesting, considering Horus also had Librarians, which meant the two would coexist within his legion.

They wore no armor as they fought, their fists flashing out at velocities that'd make bullets appear slow. Horus had figured out Cursed Augmentation, it seemed, and he was pretty good at it too, but that was hardly a surprise, given his almost godlike initial control. Their limbs almost disappeared with their exchange, hundreds of punches and kicks and elbows and knees sent at each other within mere seconds. Sukuna had the upper hand, however, since he literally had two extra arms and had perfect control over all of them. Every so often, Horus simply ran out of arms to defend himself with.

-edit-

Honestly, if he wanted to, killing Horus wouldn't take much effort.

Sukuna dodged a high kick, before then using Cleave to slice off both of Horus' legs, which the Primarch simply regenerated with a burst of RCT, mere moments later, making it appear as though he'd never lost them at all, healing so quickly as so efficiently that not even flickers of his blood reached the ground.

Fast, Sukuna noted, but not nearly as fast as Vulkan's.

"What else can you do?" Sukuna asked. Of course, there were more facets to one's power than just the negative side of an Innate Technique; after all, Technique Reversals were a thing that existed for quite a number of Sorcerers. Sukuna did not have that, unfortunately, but Horus might.

Horus shrugged. "I can open my domain now, but it's not one I'd prefer to use in a spar or in the presence of family."

Sukuna raised a brow. He wondered why, just for a moment. And then, he grinned. "Ah, I see. The blood restriction of your Innate Technique doesn't exist within your domain, does it? And so you immediately gain full control over every living creature within your expanded domain. Is that it?"

Horus blinked before smiling. "Indeed. I suppose you, my brother, may be able to open your own domain and resist its effects, but not all our siblings are capable of Jujutsu and I'd not wish to harm them."

"And you're familiar with how domain clashes work?" Sukuna asked.

Horus nodded. "In a manner. Not to the same lengths as you, perhaps, but Vulkan and I have had time to experiment with our domains and how they function and interact. It has been most illuminating."

Sukuna nodded, glancing around. Sanguinius and the Lion were engaged in a melee spar with swords. Perturabo and Dorn were engrossed in designing some kind of fortress for Terra and they seemed to be getting along well-enough, despite Malcador's assessment of their relationship. And Horus... Horus showed no signs of rebellion. In fact, Sukuna saw the opposite. Still, the Emperor had orders and he'd follow them. It'd be cool if Horus didn't rebel, however, because he'd actually prefer not to kill the bald man. For a moment, Sukuna wondered if he was getting soft. Maybe he was. He wasn't sure what he felt about that. "Fair enough. I suppose we're done?"

"Let us end our spar here," Horus said, smiling as he stretched his limbs. And grabbed a nearby towel and a glass of water, carried by the half-men cyborgs, who exuded such exquisite Cursed Energy from their misery. They were interesting little creatures, Sukuna mused. Whoever created them must be rather proud of his or her handiwork.

Sanguinius' spar with the Lion wasn't anywhere near its end and so Sukuna figured he'd just sit and watch and munch on a few snacks, but then the Khan stood up and drew two practice blades and tossed one to Sukuna, who caught one in his grasp. Sukuna raised a brow. The Khan spoke, "I'd like to spar with you, brother. We have a belief in Chogoris that you can never truly know a man until you meet him in combat."

Sukuna grinned, swinging the sword left and right. He wasn't very fond of bladed weapons – not because they were bad or anything, but Sukuna simply preferred a spear, like his Trishula. "Oh, of course."

They walked to the center of the sparring area, which was designed by Perturabo specifically for such a reason. The Khan got into his stance – light-handed and efficient, the stance of a true master of his craft. Sukuna did not recognize the fighting style, but he recognized the Khan's skill and the ease with which he moved and held the blade; it was as though the weapon was as much a part of him as his own heart. That said, the Khan wasn't known to be strong for his martial skill. No, he was strong because he knew and accepted himself and played to his strengths. And Malcador noted that, in terms of pure speed and agility, none of the Primarchs could hope to match the Khan, which was rather...

Interesting.

"I don't understand," Sukuna said, sighing and shaking his head. Across him, the Khan raised a brow. "What's holding you back? Out of all the Primarchs I've met, you're the one who's closest to truly becoming one with yourself and yet there's a tiny little thing that holds you back. And I cannot, for the life of me, understand what that thing is."

"Ah," The Khan smiled wistfully. "Though I do not understand how you could possibly know such a thing, I believe I know exactly what you speak of."

"I assume it is not something you can easily rid yourself of." Sukuna figured. A small, curious part of him wanted to ask just what it was that was holding the Khan back from fully embracing himself, from fully becoming one with who and what he was.

The Khan nodded. "Not at all. I can get rid of it anytime I wish. I simply do not want to."

"Rules?"

The Khan smiled. "No fancy tricks."

"Sure." Sukuna deactivated his Cursed Augmentation and settled into a simple stance, his two upper arms holding the sword in a two-handed grip, while his lower arms remained free, in case their battle got close enough for hand to hand. The Khan moved first. And Sukuna's eyes widened for just a moment as the Primarch seemed to disappear entirely, moving too quick for even his perceptions to follow accurately. And this was the Khan without Jujutsu, since only Horus and Vulkan, thus far, were the only Primarchs to awaken Jujutsu abilities.

Still, an opponent who was faster than him really wasn't anything he hadn't faced before. In fact, Sukuna had faced plenty of them. And in such situations, the thing he could rely on the most was his instincts, honed after decades and decades of constant violence, of victory after victory, growing stronger and smarter after each one. And so it was because of his instincts that Sukuna was able to move his sword and deflected the Khan's first strike, which would've stuck him right on the temple if he hadn't moved on time. Sukuna retaliated, but his strike was easily deflected by the Khan, then spun and began a barrage of probing attacks – none of them were lethal, but all of them held enough power to break bone and tear muscle.

Sukuna tightened his grip on his sword, feeling its weight, adjusting the tension in his stance. The Khan's form was impeccable, fluid, and grounded in the precise balance of power and restraint. Sukuna observed this as the Khan tilted his blade in an opening feint, only to vanish in a blur, leaving a faint afterimage behind.

The movement was so swift that Sukuna's eyes barely caught the glint of metal arcing toward his head. He pivoted his sword just in time, deflecting the blow with a jarring clang that sent vibrations through his arms. The Khan's sword slid off his in a controlled arc, reorienting almost instantly as he spun with a counterstroke aimed low, toward Sukuna's knee.

Sukuna's eyes flickered, narrowing. He raised a lower arm, palm open to intercept, pushing the blade away just before it sliced through his leg, using the momentum to spin back and reorient his upper sword arm. He brought the weapon down in a powerful vertical slash, aimed for the Khan's exposed shoulder. The Khan sidestepped, a movement so swift it seemed he barely moved at all, and Sukuna's blade whistled harmlessly past, digging into the ground with a dull thud.

The Khan chuckled softly, the sound barely audible. "Not bad."

Sukuna grinned, taking a half-step back as the Khan struck again, a quick series of cuts that seemed to flicker in and out of existence. The blade aimed for Sukuna's shoulder, ribs, and neck in a rapid blur, each stroke precise, controlled. Sukuna blocked and parried, his sword moving in a defensive dance, adjusting to the relentless rhythm set by the Khan's onslaught.

The Khan's movements were effortless, his form shifting as if he was an extension of the air itself. His blade spun around Sukuna's defenses with unsettling precision, grazing close enough to send brief sparks flying. Sukuna felt the sting of a near miss as the edge of the Khan's sword nicked his shoulder, a shallow cut that burned.

"Quicker than I thought," Sukuna muttered, tightening his stance, adapting. He let his instincts take over, honed through countless battles, guiding his movements with a kind of fierce intuition. His blade moved almost of its own accord, swerving with each strike, redirecting the Khan's blows with increasing precision. Each time the Khan darted forward, Sukuna met him head-on, their swords crashing together in a series of blinding exchanges.

Sukuna twisted his wrist mid-block, catching the Khan's blade and deflecting it at an angle. He thrust forward, aiming for the Khan's midsection, but the Khan merely shifted his weight, sidestepping as he brought his sword up in a sweeping arc. Sukuna's lower arm moved instinctively, intercepting the strike with an open palm, while his upper arms redirected his sword in a fluid follow-up swing aimed at the Khan's exposed side.

The Khan moved with a speed and grace that defied reason, shifting his stance to deflect the strike, his sword dancing away from Sukuna's. He countered, his blade glinting as it sliced through the air toward Sukuna's throat, but Sukuna was already reacting, ducking low and sweeping his sword upward in a powerful diagonal slash that forced the Khan back.

Sukuna took advantage, pressing forward with a relentless barrage of cuts and thrusts, each movement building on the last, forcing the Khan into a tight rhythm. But the Khan only smiled, his eyes alight with focus as he shifted his stance, becoming almost ethereal, slipping past each of Sukuna's strikes with ease. His blade wove through Sukuna's attacks like a stream flowing through rocks, smooth and unbroken, always one step ahead.

Sukuna's grin widened, his stance shifting as he altered his rhythm, throwing the Khan off just slightly. He twisted his blade mid-strike, his lower arm shooting out to grasp the Khan's wrist, but the Khan twisted free, flowing around Sukuna's hold like water, his blade cutting upward in a flash. Sukuna barely had time to block, his sword intercepting the Khan's with a resounding clash that sent tremors up his arm.

For a moment, they locked eyes, neither yielding, both breathing hard but refusing to show any sign of fatigue. The Khan's smile was faint, but it held a glimmer of respect. He flicked his blade, disengaging with a quick backstep, but Sukuna followed, adapting to the Khan's speed, predicting the subtle shifts in his stance.

Sukuna's sword slashed down in a powerful arc, and the Khan moved to deflect, but Sukuna twisted at the last moment, switching the grip on his sword and redirecting his strike to his opponent's opposite side. The Khan adjusted, blocking with a slight roll of his wrist, but his expression was sharper now, his eyes flickering with a newfound intensity.

Sukuna chuckled, a low, dangerous sound. "Getting serious now, are we?"

The Khan's blade flashed again, faster than before, as he launched a series of rapid slashes that blurred together, pressing Sukuna with a newfound intensity. Each strike was relentless, a flicker of movement and energy that Sukuna struggled to follow. But he adjusted, adapting with each stroke, his defenses tightening as he met the Khan's speed head-on, blocking, parrying, countering.

Neither gained the upper hand, each meeting the other's strikes with equal skill and force. They became a blur of motion, steel flashing, their forms almost invisible as they moved, locked in a battle of pure, instinctual precision. The world around them seemed to fade, and only the rhythm of their clash remained, a fierce, unbreakable dance that held them both captive.

AN: Chapter 45 is out on (Pat)reon!