Let's rewind a few hours.
Inside the prison where Kaido had punished Yamato, she hadn't eaten for several days.
She was starving, unbearably so, because when Kaido imprisoned her, he didn't even give her a morsel of food.
Yamato couldn't help but wonder if she was Kaido's biological daughter. What kind of father would treat his daughter so cruelly?
Locking her up in a cave and not giving her food for days, she felt as though she was on the verge of starvation.
She couldn't understand why her father was treating her this way. All she wanted was to learn more about Kozuki Oden.
"They are so secretive about Lord Oden's story. They must have altered history!"
This was what Yamato thought as she endured the confinement. During these days of isolation, the only thing that kept her going was...
She took out Oden's journal from her chest and eagerly read through its contents. Every time she read Oden's entries, she felt a surge of excitement. In her mind, Kozuki Oden was a brilliant and heroic figure. How could such a great man be labeled as a demon by the people of Wano?
Reading Oden's words, Yamato became increasingly engrossed, convinced that her thoughts were correct. How could her father use brute force to twist the truth?
She clung to her beliefs, idolizing the hero she admired. In these moments, she even forgot her hunger.
Suddenly, Yamato sensed something behind her.
"Who's there?!"
Yamato immediately became alert. Though she hadn't eaten in days, she hadn't lost her combat abilities. Every time she finished reading Lord Oden's journal, she felt even stronger.
When she turned around, she saw a shadowy figure. The figure was dressed like a ninja, small in stature, and exuded an eerie aura.
Normally, such a sinister presence would alarm anyone, as the Shadow Army was not known for being good. But Yamato was an exception.
Instead, she felt an overwhelming sense of excitement. She knew exactly what this was from Oden's journal.
This was Lord Oden's Shadow Army, his most loyal subordinates. How could they possibly be bad people if they served Lord Oden?
With that thought, Yamato's hostility faded.
"Are you... Raizo?"
Yamato sized up the shadow, recalling someone from Oden's journal, and asked.
"Yes," the shadow replied coldly. "Your faith has moved Lord Oden, so he has entrusted you with a mission. If you complete it, you will become a member of his Shadow Army, just like me."
"!" Yamato's eyes lit up. She immediately asked, "What's the mission?!"
"There is a device called the Omnitrix inside the Wano Battle Laboratory. Lord Oden needs you to obtain it. If you can't retrieve it, then destroy it, along with all the research data," Raizo said slowly. "If you accomplish this, you will become Lord Oden's subordinate."
The Omnitrix?
Yamato committed every word to memory. She was about to eagerly accept the task, but then she remembered her current predicament. Feeling downcast, she said, "I can't... I'm locked up by my father. I can't leave, and even if I did, my father would notice right away."
"Do you think Kaido's tricks can stop Lord Oden?" Raizo said with pride. "Yamato, all I need to know is if you are willing to carry out this mission for our lord."
"Of course I am!" Yamato responded immediately.
"Good." Raizo nodded, and a dark power emerged from his hand, flowing into Yamato's body.
Yamato instantly felt a surge of pain as if her body was being twisted. Her shadow seemed to come alive, rising and merging with her body.
After what felt like an eternity, the pain subsided, and Yamato stood frozen, her mind now clear about her purpose.
Raizo, with a smirk, vanished. Once again, Yamato was left alone in the prison, but she was no longer the same.
Kozuki Oden had fused her with the shadows, much like himself, transforming her into a member of the Shadow Army.
Now, Yamato was part of the Shadow Army!
What's more, Oden could communicate directly with her mind, making it clear what her next steps should be.
So, when Kin'emon led his attack on the gates, and the destruction of a few light sources created some brief darkness within the Battle Laboratory, Yamato—still small in stature—took advantage of the shadow and slipped through.
Her entire body was now cloaked in darkness, making her unrecognizable. This was because Oden needed to maintain Yamato's identity. Knowing she was Kaido's daughter, he decided to have her infiltrate the Beasts Pirates from within.
Now, Yamato, clad in shadow, entered the Battle Laboratory, wielding a sword forged from shadow. Though she had been trained with a club from a young age, Yamato, inspired by her admiration for Kozuki Oden, had also trained in swordsmanship.
Since she had to keep her identity hidden, she couldn't use her spiked club.
She had already scouted the laboratory's layout, and as soon as she appeared, she swiftly cut down the guards who stood in her way.
"There's an intruder inside!"
A loud shout caused chaos to erupt within the lab, but Yamato paid no heed to it. She was focused solely on reaching the room where the Omnitrix was kept.
Along the way, she sliced through enemies and deflected bullets with ease. Despite her young age, Yamato's strength was astonishing. Having been trained by Kaido, consumed the Inu Inu no Mi, Model: Okuchi-no-Makami fruit, and with Oden's dark power flowing through her, she was already incredibly powerful.
The guards inside, perhaps worried about damaging important research data, couldn't stop her. With no heavy weaponry like tanks or artillery to slow her down, Yamato quickly reached the room where the Omnitrix was stored.
"Is this the watch?"
Looking at the device encased in a glass dome, Yamato rushed toward it. As long as she could retrieve this watch, she would fulfill Lord Oden's mission.
But then, she froze in shock.
There was someone else in the room.
That person, dressed in black, seemed to be there for the Omnitrix as well!