After seeing Sasuke's Thunder God Sword, Kaijin no longer knew what to say to these two fools who did not know how to care for divine artifacts. Although magic and martial arts flourished on the Azure Continent, divine artifacts were exceedingly rare. Forging one required a master smith of extraordinary skill, priceless materials, the right timing and conditions, and finally a little luck. It was an incredibly difficult feat. Naruto and Sasuke had been fortunate to enter this smithy, for Master Kaijin had once successfully forged a divine artifact. He was also one of only six masters left on the continent capable of doing so.
But even as a legendary master who had forged a divine artifact, Kaijin felt an urge to toss these two into the furnace and remake them when he saw how they treated their weapons.
Kaijin took several deep breaths before recovering his usual composure. Once he had calmed down, he looked at Naruto and Sasuke and said, "Your divine artifacts are exhausted. These two weapons must have weathered a very long passage of time. Their weapon spirits spent ages asleep and were probably only awakened recently. But before their strength could fully recover, they were dragged into one battle after another. As a result, they haven't recovered at all. In fact, they're even weaker than when they first woke up. If you keep abusing them like this, their weapon spirits might fall into a deep sleep again. Worse still, they might even dissipate. If that happens, these two divine artifacts will be reduced to ordinary weapons."
Kaijin was not merely trying to frighten Naruto. Naruto remembered the Thunder God Sword from the anime he had watched in his previous life. It had been broken by his Rasengan and Sasuke's Chidori. For a divine artifact to