Onyx-Shelled Beast

Onyx-Shelled Beast is one part of the Dark Samsara's Immense Magical Energy.It was diffused from the Dark Samsaras core by The Time Judge(Along with the other three parts) in order to make the Dark Samsara weak enough to seal, but over a thousand years,it begins to gain a will of its own and starts to fuse with the Dark Samsaras core to become whole once again.

It can take on the form of its foes darkest fear.During Setsuna and her gaurds battle with the Dark Samsara it takes the form of a Gargantuan Tortoise-like monster that attacked Nidr during his time as a Guard on Nanase's Pilgrimage, at which time he couldn't even put a scratch on the monster.It's a member of  The Dark Samsara  category.