Vol 1 Skill 7 (Raikou)

And Shizuku was not fighting alone. At the same time she used Shouha Suiren, Ikki invoked Ittou Shura. He jumped from the third-floor atrium, making a decisive surprise attack from above Bischof's head.

"Tch! They had people above too!?"

But Bischof was a terrorist who had struggled through many extreme situations. Noticing the surprise attack immediately, he quickly made a countermove, reaching out toward Ikki's Intetsu with the same left hand that had caught Stella's Lævateinn before. The Judgment Ring that seized every single attack as sin―his left hand activated the ability that had rendered Stella's earth-shaking blow powerless.

Ikki's sword was only faster than Stella's sword; it was several times less powerful, so it couldn't penetrate that ability. The surprise attack must have been a blunder. Ikki's blow would surely be taken as sin and returned to him as penance―if Bischof's left hand could capture Ikki's flashing blade!

"…Huh?"

In that instant, Bischof saw something unbelievable: his own left arm flying in a spray of blood.

No matter how well Bischof's left hand rendered attacks powerless, it had no way to catch an attack Bischof couldn't see, and what Bischof couldn't catch, he couldn't stop. Ikki swung Intetsu with a speed that far exceeded human motion perception, so quickly that Ikki's own body couldn't track. It was an invisible slash, one of Ikki Kurogane's seven original sword techniques.

"The seventh secret blade―Raikou