Three months after the integration, Sasuke stood before a dead tree.
"Wood Release requires balance," Orochimaru explained. "Earth and Water chakra combined in equal measure. But more than that—it requires Yang Release. Life energy. That's what Hashirama's cells provide."
He placed his hand on the tree trunk. Nothing happened at first. Then, slowly, a single green shoot emerged from the dead wood.
"Feel the life energy in your cells. That's Yang chakra. Guide it through your chakra network, combine it with Earth and Water nature transformations."
Sasuke activated his Sharingan. Watched Orochimaru's demonstration at the cellular level. Saw how the chakra flowed. How it combined. The precise ratios required.
He placed his own hand on a different dead tree. Focused.
Earth chakra. Water chakra. Yang energy from the Hashirama cells.
Nothing happened.
"You're thinking of them as separate," Orochimaru observed. "They need to be unified. One technique, not three combined."
Sasuke tried again. This time visualizing them as a single entity. Wood chakra. Not Earth plus Water plus Yang, but something new that contained all three.
A single seed sprouted from the dead bark.
"Good," Orochimaru said. "That's the foundation. Now we build from there."
The training was frustrating. Wood Release was harder than any technique Sasuke had learned. It required a level of chakra control that pushed even his enhanced abilities.
Days of practice produced small vines. Weak branches. Nothing like Hashirama's legendary techniques.
"You're forcing it," Kabuto observed during one session. "Wood Release should feel natural. Effortless. You're still treating it like a foreign element."
"It is foreign."
"Not anymore. You have Hashirama's cells. That makes it part of you." Kabuto demonstrated—he'd received minor cell implants as well, though nowhere near Sasuke's level. A small wooden spike emerged from his palm.
"Stop thinking. Just feel. Let the wood grow naturally."
Sasuke closed his eyes. Stopped trying to force the technique. Just... let it happen.
Wood erupted from his hand. Not a spike—a full branch, thick and strong. It grew rapidly, extending ten feet before he cut off the chakra.
"There!" Kabuto grinned. "That's proper Wood Release."
From there, progress accelerated. Sasuke learned to shape the wood. Control its growth direction. Create structures instead of just random branches.
By month five, he could create wooden walls for defense. Wooden spikes for offense. Even animate the wood to grab or entangle opponents.
Still nowhere near Hashirama's level—that would take years, maybe decades. But functional. Useful.
"You're ready for combat applications," Orochimaru declared. "Let's test it."
They staged mock battles. Sasuke against multiple opponents. His new abilities made him terrifying—enhanced speed and strength from Hashirama cells, precognition from Sharingan, versatile offense from Wood Release.
He won consistently. Even against jonin-level opponents.
"Remarkable evolution," Orochimaru observed after one match. "You've adapted to your hybrid nature exceptionally well."
But Sasuke knew this was just the beginning. Wood Release was useful, but it wasn't his main goal. The Hashirama cells were a means to an end.
They were his path to the Rinnegan.