Hellfire Ruins.

The 5th level of the dungeon that they were currently in was called the Hellfire Ruins. The name naturally stemmed from the hellfire that was all around the ruined city, but it was also because of the creatures that one would find here. Almost all of the creatures in these ruins didn't have physical bodies. Since they didn't have physical bodies, they could naturally only be killed using mana. Although Atar didn't usually use magic, all he really needed to do was coat his body with mana to be able to kill the different spirits that roamed about.