"It succeeded, but not completely."
Nara Kaikei looked at the [Shadow Spiral] in his hand, infused with Yin Release Chakra.
The surface of the pitch-black energy sphere was smooth and unblemished, without the slightest rotational ripple. It was so still that it resembled an ordinary iron-ball ninja tool.
Judging from its appearance alone, no one could tell that beneath that tranquil black shell lay a rapidly spiraling current of Chakra.
"When Chakra with a wind nature is added, the [Rasengan] becomes the Wind Style: Spiral Ball, followed by the later Wind Style: Rasenshuriken."
With a thought, Nara Kaikei continuously shrank the [Shadow Spiral] in his hand until it vanished into nothingness.
"Yin Release Chakra and Wind Release Chakra possess entirely different natures.
"Wind-natured Chakra emphasizes cutting effects.
"But the core of Yin Release lies in creating form from nothingness.
"Adding Yin Release Chakra is like placing an invisible shell around the [Rasengan], allowing its effect to persist longer. It's like...
"Some kind of energy weapon!"
Nara Kaikei focused on the panel, checking the jutsu effect of [Shadow Spiral].
The stable state of [Shadow Spiral], along with its ability to severely disrupt the Chakra within a target's body...
Combined together, these two effects immediately reminded Nara Kaikei of a certain special ninja tool found in the shinobi world—
Black Receivers!
"The 'Black Receivers' that will later be embedded in Nagato and the Six Paths of Pain possess extremely powerful physical properties and Chakra-disrupting effects, while also functioning as conduits for Chakra communication and transmission."
Nara Kaikei recalled the intelligence concerning Nagato, the Rinnegan, the Six Paths, and their various abilities.
"And during the Fourth Shinobi World War, those 'immortals' also used their Truth-Seeking Orbs to create Black Receiver-like weapons for combat...
"Perhaps Truth-Seeking Orbs are the ultimate form of the Six