After the main gate of the dungeon was broken then Rein, Alexandria, Stella and Tasha were able to enter it easily and they went to take care of the dungeon's will who was definitely close to the core of this dungeon. Kagura came with Rein as his sword but Anna stayed outside the fortress to make sure that all the undeads were safe from any surprise attack.
After entering the fortress, they found out that even though this place looked very fancy from the outside, inside there was nothing. It was just a big pure white hallway and nothing else.
After walking on that pure white hallway for a few minutes, they found themselves in front of a golden door decorated with a lot of gems and jewels. In this hallway without anything else present, it stood out very distinctly.