Adaptability of the Lineage Factor

That day, Mia and the others arrived at Mosen's place as usual, but Mosen didn't come out to meet them.

"Strange. Why hasn't the jailer come out today? He should've been here by this time," Mia muttered.

"Could it be that you hit him too hard, Mia, and left him traumatized?" Ian, the One-armed Pirate, asked.

"How could that be? I know how to hold back."

"Hold back? You've been the one beating him up all this time, and he hasn't even landed a hit on you. You call that holding back?

"In that situation, even I couldn't take it, let alone him!" Michael, the One-eyed Pirate, said.

"His Observation Haki has only just awakened, and he can't use it proficiently yet. There's no way he could hit me. If I let him land a hit, wouldn't that be going easy on him?"

"You still shouldn't—"

Before Michael could finish speaking, the door to the little house opened. Mosen came out in a neatly worn Impel Down jailer's uniform, looking ready to leave.

"You're here! Sorry, I have to go upstairs today, so we'll have to skip our sparring session," Mosen told the four of them.

"So you're going out! I thought—"

"You thought you'd hit me so hard I was traumatized and had decided to give up learning Observation Haki?" Mosen asked with a laugh.

Mia scratched her head awkwardly and said nothing.

"Don't worry! I'm not the type to give up easily. I'm going upstairs because I'm running out of food."

"So soon? Didn't you bring back a cartload and a big sack of food last time? Is it because you've been sharing it with us?" Paddy asked, startled.

Mosen shook his head without elaborating.

The food was running out so quickly mainly because Mosen needed a lot of it to replenish his energy. He then used Life Return to turn that energy into greater physical strength and stamina, so he could further develop his Frozen Lineage Factor.

The meat he shared with the four of them wasn't much, actually.

"How long do you think you'll be gone, Jailer?" Mia asked.

"Not long. Just a few hours."

Hearing that Mosen would only be gone for a few hours, Mia breathed a sigh of relief. If he was gone all day, wouldn't that mean no roasted meat for them today?

Mosen didn't notice Mia's little scheme. He waved to the four of them and said, "I'm off, then. I'll give you each an extra piece of roasted meat when I get back." With that, he turned and left.

Just like last time, Mosen left Extreme Cold Hell under the watchful eyes of the prisoners.

As soon as he came up from Extreme Cold Hell, a wave of heat washed over him.

Mosen instinctively started to use cold air to block the heat, but the next second, he realized that the heat of Scorching Hell wasn't making him gasp for breath like it had the last time. His heart was beating normally, too.

In other words, Scorching Hell's heat only made him feel uncomfortable; it no longer affected his body.

Mosen was overjoyed. This showed that his recent efforts to further develop the Frozen Lineage Factor had been remarkably effective.

Mosen didn't have much sense of how his body was changing. It was like looking in the mirror every day: you wouldn't notice any major difference in yourself, but a friend you hadn't seen in a long time would always be able to point out what had changed.

By now, Mosen's physical condition had recovered to what it had been before he took part in the Lineage Factor experiment.

Someone with strong Observation Haki could sense the changes in Mosen's body. When Mia sparred with him, she could feel his life aura growing stronger little by little, though she never specifically mentioned it.

After his excitement passed, Mosen quickly calmed down. As before, he first reported to Magellan on the situation in Extreme Cold Hell over the past month, then collected food and prepared to head back.

On the way, Mosen began thinking about the Lineage Factor modifications.

When Mosen underwent the Lineage Factor modifications, there had been seven abilities: invisibility, lightning, giant strength, fire, ice, light, and magma.

Of the six groups given invisibility, lightning, giant strength, fire, ice, and magma, Mosen was the only survivor.

The light group, on the other hand, had all seven of its members survive, but like Mosen, none of them had gained any special abilities.

After awakening his memories of his past life, Mosen had formed some theories about the Lineage Factor modifications. First, Vegapunk and the others had mechanically modified his heart.

That Mechanized Heart contained Lineage Factor created by Vegapunk. With every beat, it sent the Lineage Factor throughout the body.

Once the Lineage Factor spread through the entire body, it began to alter it. Those who could adapt to the modifications gained the corresponding abilities; those who couldn't were assimilated by the Lineage Factor.

Everyone in the invisibility group had vanished from the world. Everyone in the lightning group had turned to charcoal. The bodies of those in the giant strength group had kept swelling until they exploded. The fire group's fate had been much like the lightning group's, while those in the magma group had melted completely from the intense heat. These people had all been assimilated by their respective Lineage Factors.

Mosen had avoided being assimilated because he used Life Return to confine the Lineage Factor to the Mechanized Heart, keeping the Frozen Lineage Factor from spreading throughout his body.

Later, after he came to Extreme Cold Hell, the Frozen Lineage Factor slowly fused with his body under the influence of the environment. Only then had he successfully awakened the Frozen Lineage Factor and gained the abilities of the Ice-Ice Fruit.

Taking his own situation and those of Queen and the Vinsmoke Family in the original story into account, Mosen figured there were two ways to help someone undergo Lineage Factor modifications and successfully awaken their abilities:

The first was to modify the embryo with Lineage Factor as soon as the mother became pregnant. That way, the child would be born perfectly adapted to the Lineage Factor modifications. The Vinsmoke brothers were like that.

The second was to mechanically modify a large portion of the body, like Queen, using the mechanical parts to resist the Lineage Factor's effects.

But this kind of modification required tremendous vitality. Without it, a person would die as their body tissue was replaced with mechanical parts.

And after the modifications were complete, it was hard to say whether the person could still be called human.

Mosen wasn't fond of the whole "the flesh is weak, mechanical ascension" thing.

Of course, modifying people with Lineage Factor wasn't the only way to use it.

Artificial Devil Fruits and gigantification experiments were also applications of the Lineage Factor.

Vegapunk didn't know that Mosen had now awakened the Frozen Lineage Factor.

As far as Vegapunk was concerned, the experiment had undoubtedly failed, but Mosen remembered that Vegapunk hadn't looked disappointed at all.

That suggested Vegapunk had come up with other ideas while conducting the Lineage Factor modifications. Perhaps the Mechanized Heart itself had been one of his experimental objectives.