Box of Ultimate Bliss

The Box of Ultimate Bliss is a four-sided box that is found in Kusagakure. It requires an immense amount of chakra to open.

It was thought to be able to grant the person that opens it any wish, though according to Gamabunta this is simply a myth and in reality it simply corrupts whatever enters within its confines. The box has such powers that it once allowed Kusagakure to take over the world during the time of the Sage of Six Paths. Once news of it had resurfaced, all villages stop any conflict to deal with the box. Once opened, a monster named Satori, called the puppet of the box, comes out. The puppet's job is to capture enemies and throw them into the box. Enemies thrown into the box become comrades. If no one is controlling the puppet, it goes berserk and tries to suck everything into the box. The box closes when the puppet is forced back into the box or the medium is killed. The box is virtually indestructible. Naruto tried destroying it in Sage Mode with a Big Ball Rasengan and didn't even scratch the box.

The guardian of the box, Mui, tried opening it once ten years ago with the chakra of his son, Muku. Muku didn't have enough chakra and was sucked into the box instead.