Just as Naruto and Sasuke were celebrating Danzo's death, his corpse vanished from the ground. Another Danzo appeared nearby.
"Naruto-kun, he started quietly weaving hand seals the moment he saw us," Itachi said.
Naruto flushed and shot him a resentful look. Seeing that Itachi's arm had returned to normal too, he said helplessly:
"Why didn't you say so earlier? That was so embarrassing. No wonder Danzo said he'd show us the true power of the Sharingan. What a pain."
Itachi's expression remained calm, so Naruto went on, "You're something else. You knew what was going on and still let me cut off your arm!"
Itachi could only manage a wry smile.
Naruto turned back to the resurrected Danzo. His right arm was attached again, but one Sharingan on it had closed completely.
Danzo looked rather pleased with himself. "Satisfied with the power of the Sharingan?" he asked Naruto with a smile.
Danzo was a sly old fox. Villain though he was, he never made the foolish mistakes villains usually did.
The moment he saw Naruto approaching with a group, he had quietly activated Izanagi in case Naruto attacked. It had saved his life.
Now, even as he kept talking, he wove hand seals and blasted a fierce gust of wind at Naruto.
Unfortunately for him, he knew nothing about Naruto's strength.
Naruto sneered at Danzo's Wind Release. With a light wave, he dispersed the gust and said:
"Do you really think Izanagi can keep you from dying?"
Naruto said that because he knew how to counter Izanagi: have Itachi use Izanami on Danzo.
But Itachi was badly wounded and in no condition to keep fighting.
Of course, Naruto could exchange for Izanami through the system, learn it himself, and use it on Danzo.
He simply saw no need. He could