Under the reference of the Karakuri Shield Puppet, developing the initial version of the mechanized puppet wasn't the hard part—the real challenge was sourcing the materials. Many of them couldn't be bought with money alone.
Puppet materials needed to be lightweight yet durable, corrosion-resistant, highly adaptable, and capable of channeling chakra to some degree.
Finding the right materials was like searching for a life partner—meeting one condition was easy, but fulfilling all of them at once? Nearly impossible. Worse yet, some of these requirements directly contradicted each other.
The only things that fit all criteria were the scales and bones of summoning beasts, along with certain rare types of wood.
Of course, if one didn't mind crossing ethical lines, shinobi corpses also made excellent puppet materials.
The reason the Hidden Sand Village had developed the puppeteer class of shinobi wasn't just due to the Second Kazekage, Shamon, being a genius—it was also thanks to the harsh desert environment of the Land of Wind, which housed countless armored summoning beasts. Sand shinobi could venture deep into the dunes to hunt these creatures, securing vast amounts of puppet materials and poisons.
Naturally, Umino Yoru couldn't just waltz into Wind Country to gather materials. He had to make do with what he had, repurposing existing puppet parts and metals to modify his mechanized puppet.
"The mechanized puppet can't be too heavy. I need to reduce the amount of metal in its construction."
So far, he had seized over ten Sand puppets. Aside from the Karakuri Shield Puppet, which could be modified for immediate use, the salvaged parts from the others were barely enough to assemble half of another mechanized puppet.
Still, he wasn't in a rush to buy materials on the black market. Instead, he retrieved the remains of the giant lizard summoning beast he had slain earlier.
A creature of that size—its scales and bones alone, if fully processed, could yield enough material for several mechanized puppets.
But quantity wasn't the goal. Quality mattered more. Umino Yoru decided to use all of it to craft a single, massive mechanized puppet.
With a puppet of that scale, even an elite jonin wouldn't be able to instantly overwhelm him. At the very least, he'd stand a fighting chance.
That was why he had six shadow clones working tirelessly on its development and construction.
Meanwhile, the original Umino Yoru continued his grueling training—practicing the Wind Breathing Method daily, refining Spiral Hollow Wave, and mastering Konoha-Ryū: Willow.
Wind Breathing Method & Chakra Growth
Thanks to consuming large amounts of the giant lizard's meat, his progress in the Wind Breathing Method had skyrocketed. The mysterious energy particles he absorbed and refined through his breathing had increased significantly, boosting his wind-natured chakra reserves. He was inching closer to the 0.5 "Kakashi" unit benchmark—the threshold for jonin-level chakra.
Spiral Hollow Wave Progress
With the help of his shadow clones, Spiral Hollow Wave had advanced through two stages of chakra shaping—rubber hose and steel pipe. Now, he was in the final phase: rotating and cutting through iron rods.
It was already combat-ready, with a maximum thrust range of 10 meters. However, its effective range was only 3 meters. Beyond that, the chakra shape destabilized, reducing its power to that of a Gale Palm—a sudden burst of pressurized wind.
Within 3 meters:Shatters metal and stone.
Beyond 3 meters:Effectiveness drops sharply with distance.
To fully perfect this technique, he had three possible paths:
Increase chakra output for greater explosive force. Compress the Spiral Hollow Wave's diameter, making it thinner and extending its range. Incorporate wind-nature chakra transformation to enhance its cutting power.
Each path corresponded to chakra reserves, chakra control, and wind-nature mastery, respectively.
Chakra reserves could only be improved through long-term Wind Breathing Method training. Chakra control was already at medical-ninja levels, but further refinement would take time—unless he could obtain advanced training methods from Tsunade. Wind-nature transformation was already in progress. He found that cutting leaves with shadow clones (like Naruto did) was inefficient. Instead, using Spiral Hollow Wave to slice iron rods yielded better results—though it drained more chakra.
Fortunately, his Gluttony Technique had evolved to Version 3.0 thanks to consuming the giant lizard's meat and the Wind Breathing Method's support. It now allowed him to partially absorb the summoning beast's energy, significantly boosting his wind-natured chakra recovery. Without it, sustaining such intense training would've been impossible.
Gluttony Technique 4.0 Ambition
Inspired by the summoning beast's meat, he now aimed to acquire Gold and Silver Brothers' cells from the black market. By studying how they devoured the Nine-Tails' flesh and stole its chakra, he hoped to develop Gluttony Technique 4.0.
Currently, Version 3.0 only let him partially utilize the summoning beast's chakra—not outright steal it. The extra wind-natured chakra he gained wasn't directly from the meat but from assimilating the mysterious energy particles in the air, enhanced by the beast's nutrients.
If he could push the technique further—even without reaching the Gold and Silver Brothers' level of tailed beast chakra theft—just being able to fully digest and absorb summoning beast chakra would be a massive breakthrough.
Summoning beasts might not have tailed beast-level reserves, but their chakra was still measured in "chakra tons" rather than mere units.
Of course, refining the Gluttony Technique wouldn't be quick. It required experiments, research, and Gold and Silver Brothers' cells.
Until then, he wouldn't stop consuming summoning beast meat—not just for future experiments, but also to train the Wind Breathing Method, increase his chakra, and enhance his physical abilities.
Physical Prowess & Kenjutsu
After eating so much summoning beast meat, his physique had undergone a qualitative leap.
In pure taijutsu (without opening the Eight Gates), he was now confident he could go toe-to-toe with Might Dai.
This physical boost also improved his Konoha-Ryū: Willow. His drawing speed had increased by 30%.
As for the genjutsu aspect of the technique, his talent in illusions had already brought him to Maruboshi Kosuke's level. The only thing lacking was polish in his swordsmanship.
Like taijutsu, kenjutsu required time, discipline, and experience—things he was still accumulating.
But time wasn't on his side. Elder Chiyo wouldn't wait. At any moment, she could send stronger Sand shinobi for revenge.