Land of Whirlpools.
Under the old clan chief's guidance, Naruto was practicing the Uzumaki Clan's Sealing Jutsu.
Unlike ordinary ninjutsu, Sealing Jutsu had been created to seal Chakra. Like the Three Basic Ninjutsu Techniques, it did not require a specific Chakra nature. All it required was an immense amount of Chakra and talent for cultivation.
As an Uzumaki descendant and the Nine-Tails' Jinchuriki, Naruto naturally had no problems when it came to Chakra reserves.
But talent for cultivation was harder to judge. Much of the theory behind Sealing Jutsu sounded obscure and difficult to him. After nearly two months, he had learned only a handful of sealing techniques and had not even fully mastered Adamantine Sealing Chains.
After listening to the old clan chief's explanation, Naruto turned his gaze toward the White Zetsu they had captured earlier.
He then had the old clan chief undo the seals on the White Zetsu, using them as targets for his Sealing Jutsu practice.
The practice began. Naruto gathered Chakra, and golden chains suddenly burst from his back. They danced continuously through the air, locking onto the White Zetsu that had been freed from their restraints.
Logically, after being captured over and over for practice, the White Zetsu should have completely given up resisting and become limp, helpless fish.
But White Zetsu seemed to be single-threaded creatures that only acted according to orders. While using Wood Release to intercept the golden chains, they cast the Mayfly Technique and dove underground, attempting to escape the Land of Whirlpools this way.
White Zetsu's resistance was futile. On the hard rocky ground, the Mayfly Technique could not function at all.
In barely half a minute, Adamantine Sealing Chains had caught every fleeing White Zetsu. However, because Naruto had not controlled the force properly, one White Zetsu was