Yata Mirror

The Yata Mirror was equipped to Itachi's Susanoo, in its left hand and, is considered one of the three sacred treasures. It is said to be endowed with all nature transformations and as such changes its own characteristics to completely negate any opposition.

Zetsu claimed that this, combined with the Sword of Totsuka held in its right hand, essentially made Itachi's Susanoo invincible. But can be overpowerd by the ten tails

Influence
The is one of the, together with the  and the.