This slash was Kakashi's strongest strike after combining the power of Mangekyō Kamui, and it involved the power of time-space!
That was precisely why the slash did not look particularly dazzling. It seemed utterly ordinary.
However, because it involved the power of time-space, no matter how powerful Kakuzu's combined ninjutsu was, it could not contend against it.
This was an absolute difference in level!
Moreover, rather than calling Kakashi's slash "Kamui Slash," it would be more fitting to call it "Space Slash."
In fact, after realizing that he had awakened the Mangekyō Sharingan, Kakashi had tried using the power of Kamui on its own.
However, since he had only initially mastered Kamui's power, it took an especially long windup for him to use it.
This had actually been clearly shown in the original story.
When Kakashi first used Kamui's power, he spent a long time charging it before barely managing to twist off one of Deidara's arms.
But Kakashi's original goal had been to twist off Deidara's head!
Therefore, after discovering that it was difficult to use Kamui's power alone in actual combat within a short time, Kakashi changed his approach.
He applied Kamui's power elsewhere.
This, too, had appeared in the original story, and it was incomparably terrifying.
That was when Kakashi inherited the last trace of Six Paths Obito's power and used Kamui Shuriken to directly twist off Kaguya Otsutsuki's arm!
Calling that ability heaven-defying was no exaggeration at all.
Thus, Kamui's power could be applied elsewhere.
And in this life, Kakashi's strongest aspect was his swordsmanship.
Therefore, during one training session, Kakashi suddenly had the idea of adding the power of Mangekyō Kamui to his slashes.
The result was that the slash capable of tearing through space directly sheared off the top of a mountain!
Yes, sheared