Zeref slept through the flight to Alvarez, regaining his energy quickly per the curse's typical nature. He was woken up by Irene with a stern shout. "Wake up. You can't sleep through this if you want to actually make progress yourself along with these foolish wizards you invited along with us."

Rubbing his eyes, Zeref frowned and looked around the control room. Gray was still there, but others had joined them. Natsu and his team were the expected additions, but there were people Zeref was confident he had never met. Meredy and Ultear were slightly concerning, depending on their true purpose, but the three men hanging near them were almost unrecognizable. Zeref nearly grouped the girl with dark blue hair into that category, until he sensed the magic coming from her and realized that this was Wendy, simply grown from the last time he'd seen any of the dragon slayers.

"You expanded your team." Zeref looked over at Natsu, seeing the dragon slayer grin at him.

"You got a problem with that? They're my friends too and you promised—"

He waved Natsu off. "It's fine." He looked over at Meredy followed by Ultear. "Provided that is all they are here for."

Lowering her gaze, Ultear stared down at her lap. "We don't want to cause trouble. I've already done enough damage by foolishly thinking I could stop Nirvana."

"We're here to help Gray." Meredy reassured him. "Ul likely knows the most about your demons out of all of us, so we were working with her while you slept. She kept insisting that what you were describing is impossible though - there shouldn't be a demon in existence without a book."

"Correct." Zeref studied the time mage, tilting his head. "And are you also aware of why you shouldn't dive too far into this sort of magic? This isn't the sort of topic I discuss with random individuals who just happen to be offering help."

"It's deadly." Ultear met his gaze. "Master Hades warned us to only grab your books should we even find one. He stated that even attempting to read it could be dangerous."

"And based on what we were told, you need to learn to accept outside help anyway," one of the newcomers spoke. A young boy with blond hair and green eyes turned towards him. "This magic is dangerous and while I know you're the expert, situations like this should be expected. Warnings exist for a reason."

Closing his eyes, Zeref looked away. Why did Natsu always insist on making things far more difficult? This type of magic was best in the hands of as few people as possible. Really, Gray may have been the only one of them he trusted not to use it. It wasn't even a fair comparison, considering he'd been inside the man's head for months to reach that point. Plus, there was the atypical emotional attachment — no, the unusual insistence Gray had on them being friends.

Irene spoke for him, likely realizing he was not as in control of his rage as he'd been thus far with Natsu and his friends. "He is well aware of the risks." The woman placed a hand on her hip. "His majesty doesn't trust people with the secrets to his magic regardless. Learning too much can do more than just get you killed." The enchantress looked over at Ultear. "Your master underestimated the backlash it can trigger."

"This is another type of magic that results in your curse, isn't it?" Ur met his eyes calmly. The black wizard nodded and the woman let out a sigh. "I mean, we're not idiots. None of us are going to run around trying to make more demons after you talk to us about it."

"Perhaps I could push past my distrust, if it was just your group." His eyes flickered towards the others that were new. "I have made no determination on them. In fact, I'm well aware that at least two of them are part of a guild that requires my curse to accomplish their goals - requires it and at least a minimum of two individuals with it." He looked over at Ultear calmly. "Either you withheld further information or your master was clever enough to know what information to keep to himself regarding the end result of toying around with this type of magic."

"This is the first I'm hearing of this." Ultear folded her arms over her chest. "You seemed willing to offer us a deal before, If I recall. I fail to see why this changes anything."

"That was over seven years ago." Zeref narrowed his eyes at the woman. "And for a far different purpose. Offering you a single book and explaining the inner workings of how demons function, perhaps even extending into their creation, are very different things."

"Hades isn't the sort of person to stop without gaining all of the answers." Meredy narrowed her eyes at him. "You would've been required to explain that to him."

Chuckling, Zeref shook his head. "But Precht also knows me personally. I wagered I'd be able to negotiate reasonable terms with him, perhaps an explanation regarding the details of how the spell he was attempting to recreate truly functioned." The black wizard looked over at the others. "He'd learn that my magic wasn't 'sealed' as well, an added bonus to the adventure for him."

"We're getting off topic." The other stranger spoke up, the one sitting next to the blond. "You do not trust us as we are strangers. What can we do instead to prove we will not abuse the knowledge?"

"I don't know." Zeref rose to his feet, shaking his head. "Regardless of how you work out the details, I'm not all that invested in sharing everything with you. I have some details to attend to now that I've returned based on what I've heard from my generals."

Irene smiled at him, walking over and crouching down next to Gray. "Shall I bring him with us?"

Nodding at her, Zeref began walking towards the exit, stopping once he was approaching Ultear's position near the door. "Step aside."

"Not until you give us some answers. We came here to help—"

"And you're welcome to do so." Zeref looked over at Natsu, a hollow smile growing on his face. "After all, I only stated that you would be given the chance to seek an answer before I acted on my final resort. My promises never once stated I would be working alongside of your team."

Snorting, Ur shook her head. "Showing your true colors once again." The ice mage glared at him from where she stood next to Lyon and Natsu. "No matter how much you may act like you're helping, you are never willing to include others in your actual plan. Even this vague 'last resort' of yours is kept like some deep secret—"

"No, it isn't." Zeref looked over at his brother, pausing with Irene waiting for him to continue. "Natsu knows exactly what that plan is. I'm more than happy to share that with everyone, if you truly are interested in understanding his determination to understand the impossible."

"It'll at least give us some idea as to what theories you have on resolving the issue," Jellal said.

"Yeah, that's right." Lucy grinned at him. "Were you expecting us to not want to hear it? Gonna back down from your word?"

Shaking his head, Zeref met her brown eyes calmly. "My plan consists of killing Gray, should you fail to stop this transformation." Her grin vanished at his words. "After, I will resurrect him as a proper demon, one which I can guarantee I'd have the ability to manipulate as needed to seal away the destructive nature that is clearly seen in him already."

"You—you'd betray him like that?" Erza stared at him looking even more stunned than the celestial wizard. Belatedly, he recalled he'd been entertaining himself with their misunderstandings before Acnologia arrived; Erza believed he truly was romantically involved with Gray. "He trusted you, fought for all of us to do the same. When you wished for death, Gray was the one who said there was always a better option."

His heart clenched and Zeref felt the familiar warning pain in his head as the curse sensed his brief emotional lapse. Taking a slow breath, he lifted his eyes to meet Erza's. "I value and appreciate his actions more than you can imagine." The throbbing increased and he forced himself to turn away. "But at this moment and time, I cannot allow that to interfere. If I wish to allow such events to continue into the future, Gray must first reach a state in which he can reasonably act with some degree of humanity. That is why—"

"Killing him won't accomplish that!" Lucy interrupted. "I don't get why you think that's always the right path to take. People's lives are short and—"

"Life is short?" Zeref spun around, narrowing his eyes at her. "Think for a moment who you are speaking with. I've watched everyone around me die, with very few to even come close to matching me in age." He took a step away from the door, closer to the girl. "I've killed most of those myself, both willingly and unwillingly. You claim that life is precious? That I should care about cutting their lives short?" He spun around the room, staring at the strangers. "I am exactly who history makes me out to be. That is who I have to be and if you haven't grasped that before, I will make sure you understand that now."

The group was silent after his outburst, no one willing to respond. Zeref inhaled slowly, taking a step back and looking over at Irene. The enchantress was still ready to leave whenever he was, observing his outburst calmly. "I find that difficult to believe," Lyon said at last, breaking the silence. "No matter how much you pretend, I can still see your hands shaking. Perhaps if you were being honest, the appropriate phrasing would be to say that the historical impression of you is the natural reputation gained by anyone with a curse such as yours."

It seemed like Lyon was more perceptive than Zeref had believed him to be. Meeting the ice-make wizard's gaze, the black wizard slowly nodded. "Perhaps it is." He looked over at the others. "And perhaps that is exactly who one must become to survive in this manner. Maintaining control means letting go of things other people would see as absurd to forget."

"There's more than one way to handle it," Lyon argued. Zeref closed his hands into a fist, debating if his anger was once again misplaced or justified at this man making assumptions about his own four hundred years of learning how to cope. "In case you didn't recall, we all met Mavis recently. I'll admit, I don't know her well, but she certainly has a different outlook on her curse than you."

Yet Mavis had also come to him pleading for death as well. No matter how much denial she had, no matter how hard she fought to keep a balance between friends and self-isolation, Zeref had known it would find a way to backfire. "She simply hides herself differently than I do. Smiles are just another form of a mask that I've long since given up on using."

Lyon looked at him, slowly letting out a sigh. "Fine, very well. Let's assume that is accurate. Based on my limited understanding of demons, making Gray into one just like the others tethers his existence to you, does it not?"

This, at least, was relatively common knowledge. "Yes, it would."

"Then you'd be granting him half of your own curse." Zeref stiffened at Lyon's claim. "He would live to be immortal, just like you. Perhaps it is not quite as tricky of a situation, considering he lacks the other aspects of your curse, but he would still be forced to lose his companions just as you've suffered through in your past. Are you truly willing to put him through that to ease your own guilt?"

Looking over at Gray, Zeref swallowed. It was so difficult, trying to imagine what he'd want like this. Their connection was severed and even if it wasn't, all Zeref would be able to find were the instinctual desires of a demon. Still, the thought of him never returning…Zeref felt an initial heaviness settle over him, his head throbbing dangerously given the crowd. Yet, as it intensified, he inhaled slowly and closed his eyes, remaining silent. A numbness began to overcome everything rapidly. This was the same as Mavis. This detachment was what he needed and he would not allow himself to feel anything else. Anger, guilt, grief, caring…they were worthless and intervened with the calculating mindset he needed for progress.

With the comforting numbness lingering, Zeref met Lyon's eyes. "Yes, I am." Without this, Zeref would never leave this feeling. He'd truly get lost in it, falling to the same extreme he had a century ago when he'd forced himself into isolation. Loss equated to numbing himself to avoid the curse. That, in turn, resulted in an unexpected level of control that combined with the darkest of his own plans.

This time, Ultear stepped aside when he approached the exit. No one seemed to know what to say to him. The only one who would have had a chance of talking him into sticking around was unconscious anyway. Perhaps Natsu could, but it wasn't like the dragon slayer even realized he could make such an attempt. So, he exited the airship and found himself taking a moment to try and recognize his surroundings. It appeared to be some campsite in the middle of a forest. He turned towards Irene, his brow furrowed.

"This is the location deemed as the guild hall for Crime Sorciére, Meredy's guild," Irene said. Nodding, Zeref began to walk forward. With Fiore destroyed, he supposed it made sense that their base of operations for the attack had been elsewhere. He'd simply made the assumption that they'd stay within the same continent, rather than coming here. "Do you have a specific place in mind for where to begin?"

"I need to analyze his current condition first," Zeref replied. Irene nodded, taking the lead. Trusting her to be more familiar with the layout of this place, Zeref followed and ignored the curious looks from nearby wizards. It was still relatively empty, but he still saw a few children wandering about the camp, with even fewer adults to supervise them.

Irene pushed aside the opening of a tent, carrying Gray inside. Zeref followed, watching as she set the boy down on the ground where a blanket was laid out as at least a small amount of cushion between him and the ground. "And you'll focus on Larcade and Bloodman afterwords, correct?"

Nodding, Zeref knelt down by Gray's side. His anger had been unleashed on Invel, his guilt had been internalized and focused on himself, and now, Lyon had given him the final push he needed to trust himself on this matter. In a way, he supposed he should thank the boy for determining how to be Gray's opposite at least one final time. While Gray pushed Zeref as far towards valuing life as he'd ever been since gaining his curse, Lyon pushed him directly back into realizing why he'd always been so desperate to forget.

Before he could even theorize on what to do, the first thing he needed to know was if the removal of the cuffs had offered any level of change in him. Visibly, there was nothing to see, but that did not mean there wasn't an internal shift in his energy. Closing his eyes, Zeref activated a relatively weak spell designed to enhance the…visibility, for lack of a better term, of a wizard's aura. The energy became apparent immediately, along with its flow and current areas of concentration.

A second spell formed, this one of Zeref's own design and far less useful for the general public. It served the same purpose as the first, yet this one was designed to enhance the readability of one's source of curse power. As he'd anticipated, the flow was far greater than it ever should have been for a devil slayer who'd only been able to use such an ability for mere weeks. Rather than being weakly contained in its core, struggling to even be forced from that container, it had nearly engulfed Gray's body as if it were his true source of magic.

Frowning, Zeref observed the two energies in unison. Removing the cuffs had certainly freed his magical energy, but its flow had weakened to a trickling spread that was overshadowed by the curse power with ease. Now that it had been freed, the curse power was not easily being forced back into its latent state. The lingering flow of magical energy did at least show that the transformation wasn't finalized, but it was too weak for Zeref to believe it would hold it off for long.

"The transformation isn't complete." Zeref released his spells, the enhancement fading as he studied the boy. Irene only nodded and Zeref then turned to what could become the more uncomfortable side of his analysis. Letting his hand hover over Gray's form, he closed his eyes and replaced the spell to bring out the readability of the boy's curse power. It wasn't an energy Zeref had done a ton of research in, only enough to realize it was an experimental energy source he could tap into as a potential weapon against himself.

Even with it being somewhat unfamiliar to him, he knew his demons well enough to realize that it had certain properties that differentiated itself from ethernano. Wizards specialized in terms of opening specific pathways for ethernano to flow. Demons, however, drew in curse power and that energy took on unique properties based on the host. Certain balances of hormones would trigger the largest of differences in the shape it took on, leaving each demon with a unique feel to the energy within them.

For a living person, Zeref would've thought it would be similar. People had the same biological chemicals he'd toyed around with as a basis for determining how to create different abilities for his demons, after all. They were just more natural and regulated, a balance he normally would have assumed would result in any devil slayer taking on the exact same element for their magic. Yet, it wasn't like Silver had ever allowed Zeref to truly perform an in-depth analysis of his stolen power. Now that he had access to Gray's energy, his frown deepened.

"This feels like Deliora." He pulled his hand back, staring at the boy for a moment. Irene had sat down in the corner, pulling out a journal and likely continuing her own research while Zeref focused on his task. Her contributions weren't needed yet, not when his focus was specifically on the demonic aspects of this transformation.

After a moment, Zeref reached into his requip space and retrieved Deliora's book. Carefully flipping through the pages, he skimmed through the runic characters in search for the section on the demon's biological formation. It was a necessary component in each book, required to determine a demon's physical traits and characteristics. The level of detail dictated how consistent a demon was should they require recreation at a later date. As one of his more minor demons, Deliora's physical state had not been given much focus but all of them were quite specific when it came to the necessary components to make their magic consistent.

Skimming through the runes, Zeref found himself frowning at the words. A consistently high level of corticosterone and adrenaline in Deliora was one of the main factors utilized, along with a complete absence of oxytocin that he could vaguely recall being one of the few hormones he'd typically avoided out of a refusal to allow his demons to grow attached to him. Yet, corticosterone was a hormone not naturally produced in the human body - the glands excreted cortisol instead during times of stress, a primary difference between people and other animals.

Had he performed similar experiments with cortisol? Pulling out more of his demonic books, Zeref began to skim through them to see the balances he'd relied on. It had been too long since he'd created any of them - recalling specific details was well beyond him at this point. Eventually, he found the comparison he was seeking. Lullaby, another more forgotten demon, had nearly the same balance of hormones with the exact substitute he was searching for.

"Then devil slayer magic uses a different basis for the energy's form…" He mumbled under his breath, frowning. The natural fluctuations of hormones in people should have proven that, but Zeref could at least assume it would take on the trait of the most common state in a wizard's body. Yet, Gray's devil slayer magic still took on the form of ice magic. If it followed the rules he'd understood for the other demons, that magic should have taken on some other form.

Putting away the other demons' books, Zeref instead focused on Deliora's with a frown. The book held no energy and was now just a reference for his review. Technically, he could revive the demon if he wanted…but Zeref really had no further need for Deliora at this point. Either way, there had to be something else he was missing to explain this. Before he could even consider combatting this energy with external magic, he needed a better understanding of what he was fighting. If Gray was transforming into a demon akin to Deliora, this book would be his greatest reference point.

"Don't get too absorbed yet." Irene's voice pulled him away before Zeref could begin diving into even more details. "You still have an empire to assist. This project can wait until the others are back. At least then, you'll be able to make up for stealing my time away from actually leading this place like you should be."

"The three of you manage just fine with the structure I've put in place."

"If you insist," Irene shook her head. "Is there something you need for the spell?"

"Just their books." Zeref stood up slowly, putting away Deliora's book once more. His eyes flickered towards Gray, still so uncertain as to how he'd gained the sort of power he had. In a way, it explained his actions before; Gray's instincts were gradually transitioning to align with Deliora's, one of the demons he'd designed to hunt himself down without regard to the damage caused in the process.

Irene walked past him, waiting for Zeref to return to her side. Turning around, he walked out and back into the camp for a moment. "Let's get some distance first. If you're looking to hide away your particular specialty from our recent allies, I can't imagine you want to go reviving a demon here."

That was certain. He could see Natsu and his team forming a group of their own, discussing in a small circle and planning out their own path. They would be getting nowhere, given their lack of understanding of anything. It was a shame - he'd grown familiar with their company and often found it to be beneficial to at least voice his theories to someone when brainstorming potential new spells. Still, he'd manage without as necessary.

Following Irene, he began to make his way past the tents and towards the exit. On their way, they passed by the joyful children again and their observant adults. Irene made a turn between a few tents, taking them to the opposite side of the forest from the airship. Their path was brisk and the area now empty of any more powerful wizards.

One last group still lingered as they walked. At first, Zeref had disregarded the sight just as he did with the others. That was before he felt an odd energy coming from them, a certain sort of magical power that he'd assumed belonged to a wizard before he realized there was an odd instability to it. He paused, turning towards them with a frown. Then he felt a chill attempt to pierce through the numbness he was intent on maintaining. Even from this distance, he could recognize that youthful face with long, white hair framing pale skin. Dark eyes flickered towards him, meeting his and holding his gaze for a long moment.

"Your majesty?" Irene realized his pause, noticing where his focus was directed. "Ah, the oddballs of the group. They refused to assist, claiming they were gods and that the risk was too great. I normally would have objected, but Dimaria actually sided with them in the matter before I could."

Slowly, Zeref allowed his eyes to actually look at the others. An elderly man was next to the god of death he'd only once seen as some sort of illusion when gaining his curse. Finalizing their trio was Sora, the self-proclaimed god of the sky. If Dimaria had agreed with their claim, he could already identify the elderly man. "They spoke the truth."

He looked away from them, turning towards the camp for a moment. Gray had promised that he'd find a way to make this path meaningful, giving Zeref his chance to appeal directly to the source for a means of alleviating his curse. Even when he'd been trapped, the ice mage was still moving forward. Fairy Tail had succeeded at offering him the exact path he'd assumed he'd never have. Ankhseram was here and Zeref had every chance to speak with her, the chance to claim he'd learned his lesson and would not infringe upon her domain again.

Closing his eyes, he inhaled slowly. Gray had made him promise to at least try that option, just once. Zeref had infringed upon this type of magic so many more times since his initial curse, growing careless once the punishment was already there. The past century was all he had to show to back the claim that he'd finished. Yet, right now, he was about to fall right back into it. Reviving Bloodman and Larcade directly in front of Ankhseram would make any argument he could offer pointless. If he simply did it after the curse was gone, it'd make him a liar and only bring it directly back.

"I can't do this." He turned back towards Irene, meeting her gaze calmly. "I'm sorry. Bringing them back…" He needed to be on good behavior and not toy with this sort of magic again. "They never should have existed in the first place."

"Since when has that bothered you?"

He swallowed, the numbness fading even further away. With it came a flurry of…confusion. His heart was pounding, his head hurt but not from the curse, sweat was on his skin…everything just felt like too much too quickly. A warmth came with it all, combined with the same weight that he'd been trying to fight back against for the majority of the day. "Since I realized that I've been taking the wrong approach to this all day." Gray hadn't given up on him, even when he wasn't around. Zeref couldn't just let his efforts go to waste and throw it away now, no matter how efficient it might make him at plotting a means to save the ice mage.

Just as a note, my education did not focus on biology/medicine so I apologize for any inaccuracies regarding the pseudo-science explaining away curse power/demon's magic through hormones. I did a bit of research on my own, but that isn't going to mean I have a ton of understanding on the subject. Regardless, thank you all for reading! Feel free to review and tell me what you think.