After Nojiko ate the Paramecia-type Gate-Gate Fruit, Kahn quickly helped her develop the ability to create air doors.
When Nojiko opened an air door connecting different spaces, Kahn, who had just returned to Amazon Lily not long ago, immediately left with Carina, Nojiko, Monet, and Granose, heading straight to the Calm Belt, where Impel Down is located deep beneath the sea.
This time, they travelled through a different space, so no one realized that Kahn had once again left the waters near Wano.
Upon emerging from the alternate space, Kahn found himself several thousand meters above sea level. He transformed from his human form into a dragon.
A few days later, Kahn, Monet, and their children arrived thousands of meters above Impel Down.
High in the sky, Kahn transformed back into his human form. He and Monet, with other sisters, then retrieved black jars from their bodies.
With the sound of balloons popping, a thick white mist emerged, forming a small mushroom cloud.
As the cloud dissipated, Kahn and the others donned black battle suits, each embroidered with a dragon emblem on the cloak and left chest.
The telekinetic power surrounding them slowly faded away, but even without it, Kahn and the others remained suspended in the air.
This was thanks to the floating devices from "Germa 66."
Soon after, Kahn and his crew vanished from sight—not by moving at high speed, but by entering an invisible state.
Once invisible, the air around them materialized, forming an air door that slowly opened.
After a while, the air door closed on its own.
When the air door opened again, more than half an hour had passed.
When Kahn and his companions stepped out of the air door, a large doll was standing beside them.
Kahn was unsure of the identities of these three dolls.
However, when Monet returned the diary that Kahn had given her, he opened it and, reading through it with a puzzled expression, was shocked.
The three dolls were, in fact, three of the most infamous pirates who had disappeared from the world's memory after being turned into dolls.
They were once key members of the original Roger Pirates. These pirates had forced the Marines to launch a Buster Call, led by none other than the current Fleet Admiral Sengoku, and included the "Demon Heir" Douglas Bullet, who had been confronted by Vice Admiral Garp.
Additionally, Byrnndi World, known as the "World Destroyer," who ate the Paramecia-type Momo-Momo Fruit and had been frozen in Eternal Hell for decades before Rocks became the dominant power, was one of them.
Finally, there was Catarina Devon, who had eaten the Mythical Zoan Nine-Tailed Fox Fruit and was one of the top commanders of the Blackbeard Pirates.
These three were the targets of Kahn's trip to Impel Down.
Douglas Bullet's strength was immense, making him immune to the abilities of Monet's Childlike Fruit, a Paramecia-type Devil Fruit. Either Bullet could outright avoid its effects, or he could break free from its power as easily as Kahn overcame the petrification of the Sweet-Sweet Fruit.
Before turning Bullet into a doll, Kahn and Carina teamed up to kill him. Then, Monet used the conceptual powers of the Op-Op Fruit to transfer Bullet's mind into Catarina Devon's body.
Douglas Bullet was overwhelmed and unable to use Haki to resist Monet's conceptual ability, so he had no chance to defend himself. The mind transfer was successfully completed, leaving Bullet trapped in Catarina Devon's body. Though Haki can counter the power of certain Devil Fruits, it is helpless against the conceptual power of the Op-Op Fruit. Even if Bullet could use Haki, he was now stuck with Catarina Devon's Haki, which was far weaker than his own.
In the end, Haki couldn't break free from the control of Monet's Childlike Fruit, and Kahn easily captured Bullet, along with the frozen Byrnndi World and Catarina Devon. Even Kahn, despite being a time traveller, briefly forgot about the three of them because of the Childlike Fruit's memory-erasing effects. The guards at Impel Down were even less likely to notice that these three infamous prisoners had vanished.
After successfully taking them, Kahn set out to hunt more strong fighters, ensuring he had enough materials for the Cross family's perfect creations.
Kahn then transformed back into his full-dragon form and returned to Amazon Lily with Monet's children. Once there, he instructed Monet to use the Op-Op Fruit's abilities to dismember the three pirates while they were still in their doll state. Monet then restored them to their original forms, and Kahn began extracting their blood to create lineage factors.
With their lineage factors in hand, Kahn had Monet transfer Bullet's mind, still trapped in Catarina Devon's body, into a civilian from Wano. The civilian was then turned into a doll and imprisoned. Carina then captured Catarina Devon's Zoan Mythical Beast Fruit, the Nine-Tailed Fox.
This gave the Cross family another Mythical Zoan ability. However, like Kurozumi Orochi's Yamata-no-Orochi form, Kahn did not assign this power to any family members, nor did he plan to give it to the soon-to-be-born "Perfect No. 2."
To Kahn, Douglas Bullet was as valuable as Kaido, requiring only a portion of his bloodline factor to create a powerful replica. Once the bloodline factor was used to create Perfect No. 2, Kahn would eliminate Bullet and take his Paramecia-type Composite Fruit, giving it to Perfect No. 2 to create a clone of Bullet.
After obtaining Bullet's bloodline factor, Kahn took a break from his plans, spending the next couple of months enjoying time with Robin and her sisters. After taking care of family matters, he returned to his scientific research.
Soon after, Perfect No. 2 was born.
Not long after, in the year 1517 of the Sea Circle Calendar, Perfect No. 3 was also created—a sword master incorporating the bloodline factors of Kaido, Bell, and Ashura Doji. With the birth of these perfect creations, the Cross family's top cadres were complete.
The gears of time began to turn.
Meanwhile, Ace, the son of the Pirate King, also embarked on his journey. His Logia-type Flame-Flame Fruit had been intercepted, and the position of Whitebeard Pirates' Second Division Commander, left vacant for years, had been filled. With his abilities and status taken from him, Ace's fate had drastically changed.
Whether Ace would still become a tool for the "Child of Destiny" to mature or carve out a brilliant new path for himself remained uncertain. However, his departure signalled the beginning of a new, more intense phase in the era of pirates.
Troubled times were fast approaching.
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