Ittou Rasetsu

"His personal vitality, stamina, magic power, potential, he mustered all that he had. And for an instant, he broke past his limits!!!"

Ittou Rasetsu (lit. "Blade of Rakshasa") is the Noble Art of Ikki Kurogane and an upgraded version of his Ittou Shura.

Description
During his match against Touka Toudou, Ikki with his weakened body after weeks of being slowly drugged and poisoned by the Ethnic Committee, spends the entire 1 minute of Ittou Shura into one attack, removing all normal body function allowing Ikki to transcend Ittou Shura by multiple times for 1 second.

Originally unnamed, it was given the name, Ittou Rasetsu by the spectators for Ikki's match, as they considered such a technique to be "exceeding limits beyond limits" and not within the reach of man who fell in the realm of Shura (Asura), but a Demon (Rakshasa) that exceeded humanity.

Weakness
Ittou Rasetsu drains the entirety of Ikki's magic with just one usage. After using the technique Ikki is unable to even stand up, much less fight. It even deals damage to Ikki, tearing his body.

After reaching his "Awakening", Ikki's magic power increased so that he could use Ittou Rasetsu right after Ittou Shura. This happened only once.

The backlash from the technique is now less severe after Ikki trained with Edelweiss. After improving his mana control, Ikki is able to use his Noble Art more efficiently by concentrating the strengthening of his body on the necessary parts instead of his whole body and putting the energy that would have just wastefully damaged his body on his sword instead.