One Piece: The Strongest Creature

When Luffy saw Sabo—who had regained his memory and sought him out just as Ace once had—he was in complete shock. His expression was just as exaggerated as in the original story, and he immediately burst into tears, hugging the brother he had believed dead for years.

After their reunion, Sabo took Luffy to meet Ace, who had travelled with him to Dressrosa. After five long years, the two brothers were finally together again on one of the New World's chaotic yet strangely peaceful intermediary islands.

Unaware that Sanji had quietly left with Big Mom's envoy, the three sworn brothers—Luffy, Ace, and Sabo—sat together on a wooden barrel in a quiet alley, talking for hours. Through their conversation, Luffy learned why Sabo hadn't searched for them all those years; while he had survived the Celestial Dragons' attack, it had left him with memory loss.

In the original story, Sabo regains his memory upon seeing news of Ace's death, which delivers a jolt to his mind. In this alternate timeline, Sabo also recovered his memories because of Ace. While leading the Revolutionary Army in liberating a country, Sabo encountered Ace, who was travelling in the New World with the Spade Pirates without a permanent base. Years had passed, and both had grown into adults, but Ace recognized Sabo instantly. Stunned, Sabo's memories of Ace and Luffy came flooding back.

Once they reconnected, Ace was deeply grateful to Luffy's father, Monkey D. Dragon, for saving Sabo. Raised with Makino's guidance, Ace felt a sincere gratitude toward Dragon, even though they had never met. Taking advantage of some free time, Ace accompanied Sabo back to the Revolutionary Army's base, wanting to understand more about Sabo's life over the years.

For the past few years, Ace had stayed with the Revolutionary Army, supporting Sabo while giving his crewmates valuable training. He even trained further under Monkey D. Dragon, honing his Haki and physical abilities through sparring with Sabo. Ace's skill in Armament and Observation Haki grew substantially, achieving mastery over future sight thanks to training with formidable opponents like Charlotte Katakuri.

Sabo, often seen as the "weaker" of the three brothers, had nonetheless mastered both Armament and Observation Haki as a teen, even learning advanced Armament techniques. Ace's natural Haki potential, however, was exceptional—stories claim he learned Armament Haki in a single day. Already polished by Rayleigh, Ace's raw talent truly began to shine, mastering advanced Observation Haki with future sight and Conqueror's Haki infusion in his twenties.

The three brothers, each powerful in his own right, were finally reunited and stronger than ever, ready to face the challenges of the New World together.

At twenty-one, Yamato had also mastered Conqueror's infusion, proving her strength. Though her skill didn't match her "brother-in-law" Ace's, who had unlocked advanced Conqueror's Haki and fruit awakening at just nineteen, mastering such advanced Haki at twenty-one showed Ace's undeniable potential as the son of the Pirate King.

While Ace's physical prowess and Haki reserves might not match those of the "super-monsters," he has become a prime candidate for second-in-command of the Revolutionary Army, even surpassing Sabo in some ways. In nearly any major faction besides the Cross Guild, World Government, or Naval Headquarters, Ace would hold the role of second-in-command by sheer power alone.

Having inherited Roger's unyielding spirit instead of his "Voice of All Things" ability, Ace—who never ate the Mera Mera no Mi—has unlocked his full Haki potential, embarking on an extraordinary path. Yet, despite his remarkable talent, Ace's Haki still falls slightly behind that of Luffy and their father, Roger. As the two "sons of destiny" from successive generations, Luffy and Roger not only have astounding Haki but also possess the unique power to hear the "Voice of All Things," a rare, natural ability akin to Observation Haki. Only those with this gift are truly considered "the chosen ones."

Even without this rare ability, Ace's strength has grown comparable to Sabo's in the original story, where Sabo ate the Mera Mera no Mi and fought Admirals on even terms for short bouts. With further development of his physical skills, resilience, and Haki reserves, Ace is likely to reach Admiral-level power without the need for a Devil Fruit. But if he were to eat a Zoan Mythical Devil Fruit, his power would surge, placing him among the world's top fighters.

In this timeline, the strength ranking of the three brothers is clear: Ace is the strongest, followed by Sabo, with Luffy trailing in third. Against Sabo's advanced Haki mastery and his seasoned combat skills, Luffy, even in Fourth Gear, struggles to keep up. Just as Rayleigh overpowered Fourth Gear Luffy with ease, Sabo would only need a few well-placed advanced Armament Haki strikes to bring Luffy down.

After the three brothers finished talking, Luffy planned to introduce his crew to his brothers. But as soon as he returned, he learned from Yuba—who had freed himself—that Sanji had left with Big Mom's crew. Discovering that Sanji was forced to go rather than leaving willingly, Luffy immediately set aside his plans to head for Wano and decided to go to Whole Cake Island to bring Sanji back.

Knowing the dangers of facing one of the Four Emperors, neither Ace nor Sabo wanted Luffy to go alone. So, Ace rallied his Spade Pirates while Sabo gathered his men, and both set off with Luffy for Whole Cake Island to rescue Sanji.

The brothers had barely reunited, yet they were already about to invade the territory of the Pirate Queen, one of the New World's most powerful emperors. If they manage to escape Whole Cake Island unharmed, their reputations will skyrocket just as Luffy's did in the original story. Should they stir up chaos and escape unscathed, a part of Charlotte Linlin's decades-long prestige will undoubtedly be overshadowed by the feat.

The world would have no choice but to focus on them!

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