Several Months Later | Somewhere in Hueco Mundo
(Third Person POV)

In an empty, wide cave deep within the furthest corners of Hueco Mundo's great desert sat a sole Arrancar—soul devouring monsters that have ripped off their masks to become greater. This was Coyote Starrk, a being strong even amongst the Arrancar—an Espada, and the Primera at that.

The usually stoic Arrancar had his face scrunched up in concentration while he attempted to control his breathing, devoting all his focus on the sole task.

These exercises were among the many taught to him by Aizen Sōsuke—A powerful Soul Reaper who became the leader of the Arrancar—shortly before he joined the ranks of Las Noches in order for him to develop his Reiatsu control.

Why was such a powerful being struggling with mere energy control? Long story short, he currently had more than twice the previous reiryoku output compared to before merging with Lilynette Gingerbuck.

If Starrk failed to control this new power, two things are guaranteed to happen:

1)His overwhelming power would continue to kill everything around him.
2)He would explode because his body wouldn't be able to handle all of his energy.

The point was, this was important.

The sound of his breaths echoed throughout the empty, hollow cave, followed by the occasional dripping of water.

While everything should have been going great, Starrk found himself unable to concentrate. A strange thing because before, he could effortlessly slip into a state of concentration (despite what most would think).

So he tried his best to focus on his breathing.

He breathed in, feeling the cold air of Hueco Mundo rush into his lungs leaving him feeling somewhat light headed.

Exhaling, he let out a sight of breath, feeling the same air escaping from his lips.

It was a relaxing exercise, it's just that after a few moments his mind would drift off and he'd lose his concentration and release his reiatsu.

It was both painful and frustrating.

And with that his focus wavered.

He winced as the energy stored within him was forcefully expelled and burst forth from the pores of his skin, engulfing both his body and the cave in bright blue flames of energy that chipped away at its structure.

His reiatsu flickered around him like a hungry fire that splatted light against the cave walls, casting a glow that seemed ready to consume its surroundings.

Letting out a sigh of frustration, Starrk decided that he would take a much needed break from the exercises. He had been cycling through several in order to see which method would be the most effective in accomplishing his new goal.

Over the past three months since he'd first returned to Hueco Mundo, the Primera had spent 90% of his time "training" and the rest either resting or eating.

Thinking back to his "little" problem, when he first starting this meditation he first thought his power was identical to how it was before he became an Arrancar. But to his shock, he saw that he possessed much more, growing to rival even the likes of Aizen.

'Though if we were to fight, I don't think I'd be able to win. Aizen's Kyōka Suigetsu and his general skills gave him an advantage that not even my Soul Splitting may be able to rival.' Starrk came to realize at the time, surprising himself by feeling anger at the thought of losing. It wasn't like him and he quickly brushed it off, thinking it was his frustration at the time.

Back on the topic of his reiatsu, the best theory Starrk could come up with was that due to him growing in power as an Arrancar (Los Lobos) and then merging once more, he regained the power his original self possessed along with the boost of his Resurrección training—something every Arrancar would need to undergo before they are granted the rank of Espada.

Along with his new raw power that threatened to kill him, Starrk also discovered a way to (somewhat) control his new regenerative abilities which rivalled an Adjuchas in terms of speed. With this, he could even keep his approaching doom at bay for a little while longer before his body began to deteriorate.

But honestly, this training was frustrating and far more difficult than he'd initially anticipated. Sure, as a Vasto Lorde he had trouble controlling his power but that was because he hadn't once even attempted the act. Once he became an Arrancar, the difficulty decreased exponentially and with Aizen's help, he'd reached an average reiatsu control level in under four years.

There was no comparing how much of a hassle the task was now. If he had to put it in numbers, his time as a hollow would be a 5 out of 10, Arrancar? 1 out of 10. Now though? 15 of out 10.

Along with that, imagine 4 years of progress gone over night. That realisation was very frustrating. He'd even apologized to the cave. The Primera was starting to believe that he might as well just explode already.

Yeah, this wasn't one bit easy and this caused Starrk to start looking for shortcuts and other methods to shorten this mind-numbing process.

His final conclusion? It would take much longer with his new power then he anticipated.

Looking back, he probably should've tried to be more careful. He almost ended up destroying the cave seventine times in his annoyance.

Speaking of the cave, it was quite concealed and made the perfect place for him to let out his frustrations AKA his Reiatsu. While not very comfortable, it was good enough to be called home.

It even protected him from the terrifying sandstorms that always got sand in places.

Deciding that he'd wasted enough time already in his thoughts, the Primera Espada sighed and slipped back into his new favourite stance. This time he'll try the next method.

After arriving and settling into his new cave, Starrk began planning out steps for his training. He decided that the first step was to feel his reiatsu. Unfortunately for him, that was like trying to grasp and carry a pool of water with his bare hands.

It keeps slipping. He grumbled.

And as you can probably guess, the Arrancar was still on step one.

This new technique was called the "Waves Method" and was highly affective for the Shinigami. It involved slowly releasing one's reiatsu in controlled waves before slowly reversing the process until the reiatsu is contained. It helped with both suppression and the initial "grasping" when one first begins training.

He had only attempted this method once before and he ended up losing control, which forcefully withdrew nearly all of his reiryoku, and it lashed out at his surroundings, destroying several cave walls and trashing his little home.

That was over 2 months ago, and Coyote Starrk hoped to have improved. So he spent the next several hours in barely kept concentration.

This was becoming a frequent and annoying occurrence for the Arrancar. He'd spend hours on end working on this, even forgoing sleep in hope for some improvement. 'It's somewhat working', his concentration nearly wavered at the new emotions.

Before the training, trying to control his reiatsu felt like trying to calm a raging storm by yelling at it—simply futile, impossible to accomplish. But now? It was still very difficult, like trying to keep yourself from being swept away by huge waves in the deep sea—difficult but still doable, a visible improvement.

Inhaling softly, he let himself fall back into the daze of releasing his reiatsu in waves.

Several hours later, blue-grey orbs snapped open to reveal tired, frustrated eyes. His brown hair was even more unkempt and disheveled, falling just past his shoulders, having grown to reach just past his shoulders. The Espada wore only a torn, worn-out pair of black, skin-tight pants, leaving his torso bare. His uniform had long since been destroyed over the past few months.

Despite his unsavory state, the Espada did not bat an eye and instead got up. He was overjoyed that he'd been able to focus for so long but the snail pace this training was going at overweighed the feeling.

Brushing himself off, he began to place one foot in front of the other, his footsteps slow as his reiatsu flickered around him like its own being.

He stepped out into the grey, barren desert stuck in an eternal night, the area indistinguishable from the rest of the realm. Rocks scattered around the cave was imbedded into a large hill of rock and sand, covered by rock formation. And while trees were scarce in the area, they were as tall as humans yet as rare as Vasto Lorde.

While still maintaining a vice grip on his energy, Starrk let himself relax and his reiatsu flowed smoothly around him, flickering with just enough power to not destroy anything

Once again, he fell into deep thought thinking of ways on how to control this raging power. Now a days, it was the main thing occupying his mind. He didn't really have anything else to think of besides Lilynette, the Espada—reminiscing about the past.

It was the only time he truly got to relax, when negative thoughts flushed from his brain. It lead him to think about his time as a Hollow. Of how chaotic and uncontrollable it was, how lethal he was back then, even before "his" evolution.

'Come to think of it, I don't really know who I was back then. I remember everything clearly but thoughts and feelings, my personality back then are gone. Like I was a completely different person before splitting my soul.'

Over a decade ago, Starrk, or the Hollow that would become both him and Lilynette tried multiple times in a futile attempt to get his power under control in order to stop killing everything around him. His failure to do so would be the start of his connection to solitude. Loneliness.

Shaking his head to clear away those thoughts, he tried to think on the bright sight. 'But now, compared to back then I have experience. Much more than before, so at the very least it should not be impossible an impossible task, just an extremely challenging one.'

And suddenly a thought popped up in his mind. 'What if instead of thinking like a Hollow, why not look at it from the perspective of a Shinigami.' Aizen's viewpoint always seemed different compared to the Hollows, and that wasn't even considering his own intelligence. It was the same with Gin and Tōsen, though they were almost as tricky as Aizen to read.

Shinigami would not try and brute strength it, they'd think back to training and past lessons, to see for any solutions… The Primera suddenly came to a realization as a memory came to the front of his mind.

One day, during his reiatsu training with Aizen, the traitorous Shinigami told him about how all powerful Shinigami would seal the majority of their reiatsu into their Zanpakutō when sealing their released states. It was why they seemed so much more powerful when they released into states like Shikai or Bankai when in fact these releases only granted them their unique abilities.

While Arrancar though, their release granted them the power they lost as Hollows as well as their unique abilities. Starrk's thoughts raced as he began to formulate a plan, a bridge between the understanding of a Shinigami and the raw power of an Arrancar. If he could channel his reiatsu like they did, perhaps he could achieve the control he so desperately sought.

Now this would have definitely worked, except for the fact that he did not have a Zanpakutō. While yes, he possess a blade, that was simply a katana given to him by Aizen. The closest thing to one would be Lilynette, and she wasn't exactly with him. She was the only way he could access Los Lobos, so that method wouldn't exactly work.

'This is frustrating.' Starrk thought with a grunt as he gazed upon the vast landscape stretching out before him far beyond the horizon of his view.

It made him feel helpless, like he couldn't do anything. Like he couldn't accomplish anything.

And so frustration turned to anger.

It was a foreign feeling. It told him to do something impulsive, and Starrk having no experience with such an emotion, obeyed.

So he gave into his rage and decided to let out his frustrations.

A bright azure orb of energy formed, flashing with dangerous and uncontrolled energy. A cero.

Having nothing to stop him, the Primera unleashed the blast which transformed into a massive beam that seemed to want to devour anything in its path. Including a mountain.

"BOOM!"

His ears rang under the force of the resulting explosion, he ducked down for cover to avoid the force of the resounding shockwave that nearly launched him back into his cave, making sure to protect his ear drums.

Dust rushed throughout the area, concealing the destruction of the beam and momentarily blinding him to the world around him.

Quickly recovering, Starrk stood up, squinting to see past the fading layer of dust.

Once the dust settled, surprised wouldn't even come close to what Starrk was feeling at that moment: Shock, Pride, Horror

A colossal gaping hole ran through the mountain. Its circumference ranging of about a mile wide, the resulting hole penetrating the gigantic structure, having left damage to the land beyond, wiping the area of life. Blue fumes of reiatsu was emanating from the destruction.

If one had to see it, they would've thought it was the result of a meteor.

Once his mind fully registered the event, his eyes slowly widened as the Primera realized the true extent of his power. A regular cero from him in this state had as much destructive power as a Gran Rey Cero.

He found himself wondering why he didn't take the time to experiment with this new power instead of dreading it enough to keep it on a leash. The strength he now possessed was incredible.

The sense of pride that the Arrancar felt that moment was only matched by the horror he felt at the destruction he may accidentally cause. It was only then did he realize that his anger was gone but his desire to get the reiatsu problem under control only doubled.

It was strange. He'd never been one to get angry or frustrated before. He thought back to the strangeness of his reiatsu guiding his mind. Was that the cause? His reiatsu changed because of the merging which is now affecting his mind and causing these… mood swings.

Similar impulses—sudden feelings and urges began occurring during the months following the events of Fake Karakura Town. He'd be blind not to notice them after this long.

At first he thought it was trauma—a way for him to deal with the loss. But it was something different entirely.

Another thing that surprised him was that he didn't feel like lazing around. At all.

In fact the idea repulsed him—laying around on his ass doing nothing. It felt like he'd be living in vain of Lilynette's sacrifice. He wanted to honour the petite Arrancar, if nothing else. To do that he had to live, and to live he needs control.

That determination from all those months ago still flowed through his veins, pushing him on, telling him to change, to get something done for once.

And quite frankly, he agreed. It was needed if he wanted to actually grow. And he sure as hell is going to grow.

He knew it wasn't grief or a sense of duty causing the determination. It was his soul—it was similar to those mood swings. So Starrk came to one conclusion, merging was changing him.

He was no longer just Starrk, he was also Lilynette. But he was also neither, the person he was becoming was someone unique, their own person. Not unlike his original self.

It was sort of refreshing. Both the destruction and the enlightenment. Knowing that maybe he truly wasn't alone helped too.

Starrk's mind eventually went back to the matter at hand and he came to a decision.

He was going to figure out how to regain Los Lobos. Or at least a similar method to the shinigami. He needed to think outside of the box, to get a different prospective on how to go on about this.

However, that didn't mean he would stop his usual meditation sessions—because while slow, it was still crucial for both his and others survival. Instead, Starrk planned to incorporate these new experiments into his routine.

He didn't plan to stop until his control was perfect. When no one would die.

So Starrk spent the next few days focused on experimenting with his reiatsu and techniques. What did he discover?

For some reason his Hierro wasn't functioning. At all. That sure was something to discover, had him worried for a while. Until he remembered his regeneration. 'Is this like a trade-off? Weird.'

Second was that he couldn't use abilities like bala and other energy related abilities outside of cero. Apparently, he kept overcharging it every time. It ended with the blast exploding in his face. That left Cero and Gran Rey Cero in his offensive arsenal with Cero Oscuros and Cero Metraletta being "locked" to his Resurrección.

Other than that, Descorrer, Pesquisa, Carnada, and Sonído were the only techniques available to him.

Carnada seemed to work much less efficiently compared to before. It would only summon Vasto Lorde-level hollows, it seems anything weaker than that was too scared of his power. But envío seemed even stronger. So you win some, you lose some.

It actually left him with two Vasto Lorde hanging around. It was awkward while waiting for them to return to wherever they were before the summoning.

His conclusion was that he was more cooked than he thought possible. He needed to get this damned power under control.

"At least it was a relaxing week…" He murmured to himself, feeling at least satisfied.

(Chapter End)

Author's Notes:

• Carnada(Bait) - A non-canon(ish) two-step technique that all powerful Arrancar are able to use. It involves flaring one's reiatsu to draw Hollows to your location. Carnada makes up step one.

• Envío(Submit) - The second step of the technique which involves forcing the Hollows to submit to you using your superior power, allowing these Arrancar to use the Hollows in battle to support them.

Also just to clarify: Starrk's reiatsu = Aizen(Arrancar Arc). Which means he is not strong enough(yet) to negate Kyōka Suigetsu and would lose against Aizen's kido, swordsmanship, etc.

Thanks for reading.