Tarisa Warinai 
DUNGEON DIVE: Aim for the Deepest Level Volume 8 (Light Novel) [EPUB ebook] 

A thousand-year-old contract. A mission to inherit the power of the apostles. A continuous game of battles between heroes and monsters.

In the Boundary War, everyone swings between “fate” and “birth, ” and there is no longer anyone to stop Palinchron’s plan to fulfill his contract. However, having finally captured Palinchron on the battlefield, Kanami challenges his bitter enemy in order to stop the recurrence of what happened a thousand years ago.

The Worldcrown Array is activated, purple amethyst magic fills the area, and once again the Trial of the Twentieth Floor begins! At the moment when the oath and destiny residing in his heart are fulfilled, the boy will be the one who discovers the deepest truth.