Mukōjōchū Muramasa

is a technique of Kōga Kuchiki's Zanpakutō, Muramasa.

Description
Raising his Zanpakutō so the blade points directly upwards, Kōga calls out the name of the technique, creating a massive explosion of purple Reiatsu. As the dust clouds settle, Muramasa begins to manifest, initially covered in a purple haze which disappears as he becomes a physical presence. Muramasa can now use his abilities directly on Kōga's foes.