The Martial Unity

The rabbit king continued to gather even more speed as it grew faster and faster. Rui would be lying if he said he wasn't impressed by its sophisticated hunting style. In fact, if he hadn't known better, he would have suspected that it was a Martial Art technique.
However, he knew that it wasn't.
It was more so an evolutionary innate ability.
Their entire physiology and anatomy were structured in such a way that it lent itself to allowing them to make extremely efficient and effective applications of their power. At the moment, The rabbit was displaying efficiency of application of power similar to Rui's Outer Convergence.
The difference was that Rui's Outer Convergence was a set of coordinated movements, that he mastered within micrometers and microseconds of absolute accuracy, with timing and placement such that the sum total power generated by the body across the body could be redirected and leveraged in a single point or part.
The rabbit king accomplished something similar to that based purely on
physiology and anatomy, limited only to jumping and vibrating purposes. That, combined with the fact that it had a body that was stronger than his despite being smaller due to the fact that it was a literal monster, meant that it could output devastating power and speed.
Unfortunately, its opponent was Rui Quarrier.
"Speed Void."
Instantly, Rui activated the Yggdrasil System, bending heaven and earth to change. To become hostile to speed itself.
The drag coefficient altered, becoming a dynamic variable such that the drag force would rise tetragonally relative to speed.
WHOOSH!
The rabbit king slowed midair as a huge burst of air exploded from it in resistance. The rabbit shook visibly, stunned by the fact that Rui somehow managed to steal its speed from it!
Yet that wasn't all.
"Temporal Disharmony." Rui glared into its eyes as he activated.
WHOOSH
Rui appeared before it in a flash.
BAM BAM BAM!!!
He pummeled the rabbit kind with a torrent of powerful blows. Behind each fist was the full power of Outer Convergence, Fire Breathing, and Reverberating Lance, unleashing devastating impacts upon the rabbit king.
Stripped of its speed, the rabbit king was almost crippled.
Rui knew that.
However, he had no intention of taking a safe and slow approach. It might be what he would have done in the Human Domain, but in the Beast Domain, such measures were too slow and energy-consuming.
BOOOOM!!!
He blasted the rabbit king's head with a powerful double-fist axe blow with the full power of Hypertrophic Surge.
CRACK!
The rabbit kind shivered as its pupils dilated and its eyes rolled upward.
A pool of black blood formed underneath its head as its body grew limp.
"Huff..." Rui heaved a sigh, deactivating all his techniques.
It was a powerful foe, one that had given Rui a decent challenge even if it could not bring out his full power. Of course, that did not reflect its power poorly, but it spoke more to just how strong Rui was currently.
Unless one was an absolute monster like Gatekeeper, defeating Rui while in the Senior Realm was an extremely difficult task. And even then, Rui had managed to overcome the Gatekeeper, even if extremely narrowly.
This battle once more reaffirmed his dominance in the Senior Realm. Yet, Rui knew that in the Beast Domain, power did not correlate with survival entirely. There were powerful, large beasts that made themselves prey with how much attention they drew to themselves such that even the smallest opportunity was exploited by everything to collectively bring it down.
WHOOSH
He immediately leaped away, returning to where Kane was. Thankfully, as he had predicted, Kane could handle the army of Squire-level creatures pretty well. They could not sense him so long as he used his Void Step technique. While his power was low, his twin daggers were more than strong enough to slice and dice through the king rabbits that tried attacking him.
"Help me out!" He complained. "These things are endless!"
It was difficult for him to evade them since they were omnidirectionally swarming him. There was no opening through which he could squeeze through to escape. The more he killed, the more they jumped in. If not for the fact that he killed dozens every second, they would have long swarmed him.
THWOOM!!!
Rui launched a powerful Might Roar Flash Blast, blasting a hole through the many that sought to overrun Kane through sheer numbers. Kane immediately exploited the opening to leap through and get away.
With Void Step, they couldn't even sense him.
"Thanks, man," he heaved a tired sigh. "I did not ever think that I would face that much trouble with Squire-level beasts."
"Quantity has a quality of its own," Rui replied. "Hundreds of thousands, if not millions, of low-grade Squire-level creatures, are not a Squire-level threat; they're Senior-level because they can drain the Martial Heart and mog you down when you're exhausted."
It was the biggest shortcoming of the Martial Heart and the Senior Realm. The two of them activated their respective stealth techniques, immediately moving
away from the region.
"I didn't even get to try the meat," Kane grumbled.
Rui returned with the corpse of the rabbit king in the distance. "Well, this one had
grown much stronger over time. Has higher nutritional value and was cleanly killed less than a minute ago, so..."
He shrugged. "Might as well. You've spilled so much blood that they won't be
able to track us."
"Nice!" Kane grinned.
They stopped some distance away from the region before finally pausing to take
a break. Rui heaved a sigh, drinking some water while Kane skinned the rabbit and drained the blood.
"This meat better be worth it, not gonna lie," Kane remarked as he roasted it over
a fire.
"It wouldn't have needed to if someone had been so rash and careless," Rui glared at him. "This isn't a vacation. This is the Beast Domain."
To his credit, Kane relented. He knew he had messed up in his excitement.
"I'll make it up by roasting this rabbit immaculately," he promised.