Chapter 11: Methods to Raise Temperature
The second half of the Grand Line—the New World.
On the calm sea, the Spade Pirates' ship drifted leisurely beneath a clear blue sky. Portgas D. Ace lay stretched out at the bow, his iconic hat covering his face, arms folded behind his head as he napped peacefully.
"The sun feels so warm," he murmured, lifting his hat slightly to squint at the sun. A gentle smile tugged at his lips. "Come to think of it, this is the first time since I traveled through time that I've truly basked in the sunlight. It's… surprisingly comfortable."
He chuckled to himself. "It feels different. Like this sun is warmer than I remember."
Just then, Gambi approached, a look of confusion on his face.
"Ace, didn't you say you wanted to find Red-Haired Shanks and then challenge Whitebeard, the strongest man in the world? Why did we suddenly turn around and head back to the Sabaody Archipelago?"
Ace sat up, stretching his body as he answered, "I suddenly remembered something. There's someone I need to meet at Sabaody. Also… after fighting with the Donquixote Family, I realized something."
He looked out at the horizon. "Whether it's Shanks or Whitebeard… we're not ready for them yet."
"Don't talk like that!" Gambi barked, smacking Ace's shoulder hard. "You're our captain. You're the man who's going to become the Pirate King!"
Ace grinned, unbothered. "Relax, Gambi. I'm just talking about the present. Sooner or later, I'll surpass them both. That's a promise."
Though Ace had only been out at sea for half a year, he was no rookie adventurer like Luffy. Before setting sail, he already had a clear goal. And once he hit the seas, he climbed to the New World through sheer strength and unrelenting momentum.
In the original timeline, Ace had been on his way to meet Shanks. After that, he met Whitebeard, was swayed by his charisma, and joined his crew, becoming captain of the Second Division. Bearing Whitebeard's name, he made waves across the New World.
But in the pursuit of Blackbeard, he was defeated—an event that triggered the Summit War and eventually cost him his life.
Ace had no intention of repeating that fate. This time, he was going to grow stronger before he even thought of facing men like Shanks or Whitebeard.
With the Mera Mera no Mi in his arsenal, he saw two clear paths to power. One was further developing his Devil Fruit—which he had temporarily set aside. The other was mastering all three forms of Haki. And there was someone at Sabaody who could teach him exactly that.
"That's the Ace I know," Gambi said, proud and reassured.
Ace raised a hand toward the blazing sun, fingers curling as if to grasp it. "Hey Gambi," he said thoughtfully, "don't you think the sun feels especially warm today?"
"Warm?" Gambi blinked. "Isn't that normal? It's the sun."
"…Maybe I'm imagining things," Ace muttered, then lay back down again. "Go on. I'll just enjoy the sun for a bit."
---
The next day, the weather remained clear. Once again, Ace lay sprawled at the bow, basking in the golden sunlight. This time, though, something was stirring deep inside him.
Fwoosh.
A small flame flickered to life on his fingertip. Ace stared at it, his brow furrowed in concentration as the flame shifted in color and heat.
"601 degrees…?" he whispered, astonishment flashing in his eyes. "So it wasn't my imagination. The flame's temperature went up by one degree."
Until now, no matter what method he tried, Ace hadn't been able to raise the elemental flame temperature produced by his fruit. And yet after one full day in the sun, it had increased—just like that.
If that didn't excite him, nothing would.
Standing up, Ace whispered, "So after basking in the sun for a day, the elemental flame limit of the Mera Mera no Mi rose by one degree… That's the method? It's that simple?"
"It's not part of the fruit's ability—so this must be my cheat, my golden finger, the perk I got when I came to this world."
"But the increase was just one degree after an entire day. Is that a fixed amount? Or can it change?"
Ace stared at the sun overhead, his gaze intense. "Well then… Until we reach Sabaody, let's test just how much love the sun can give me."
---
In the days that followed, Ace did exactly that.
As long as the sun was out, he made sure to soak in its rays for at least one hour daily. And his tests confirmed it: his flame temperature increased by exactly one degree per day.
No more. No less. Even if he basked longer, the effect wouldn't stack.
So then he tested something else—altitude. And to his surprise, he found that the closer he got to the sun, the greater the temperature boost.
He began recording data.
At sea level, one hour of sunlight yielded a +1 degree boost.
At 1,000 meters, the same hour yielded +2 degrees.
At 2,000 meters, +3 degrees.
And at 3,000 meters, his flame temperature increased by 4 degrees with just one hour of sun exposure.
The increase stacked, and he saw no sign of a cap—yet.
Hovering three thousand meters above sea level, Ace partially transformed into fire, using jets of flame to hold himself aloft. The heat from the sun poured into him, making his blood boil with energy.
But after one hour, drenched in sweat and dangerously drained, he lost control and began to fall.
Boom!
He landed heavily on the deck below, collapsing flat on his back. The crew barely reacted—they were used to their captain's strange training regimens by now.
Gasping for breath, Ace muttered to himself, "Three thousand meters… That's my current limit. I can't stay up any longer than that—not yet."
"But even 4 degrees per day… it's still too slow."
He stood, his eyes narrowing at a drifting cloud high above.
"If I could train up there…" he whispered. "Whether it's Haki or my Devil Fruit, everything would improve faster."
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