Board Thread:Fourth Databook/@comment-4271790-20141104211032/@comment-945885-20141105015557

The full name of Kaguya's portal ability:, named after the slope that leads to the underworld in Japanese mythology; the section header calls it a "gateway to the underworld" (冥府の門口). It allows her to create an opening in space through which she can freely enter and exit any of her six dimensions, and it could be said that this technique was the original (元祖, original, founding, pioneering) space-time ninjutsu. It goes on to describe it as being similar to kamui in that it can be used to trap enemies, for transportation, and so forth (all the things we say Kaguya doing with it).