As Asta and the others were chasing the creature that lived in the cave beneath the Yultim Volcano Trail, they happened upon a dungeon. They were then ordered to explore the dungeon by the royal capital, so they split into groups and went in. They head in with Leopold and Vice Captain Randall, but those two end up running into the creature from earlier. They work together but cannot defeat the monster, which makes Leopold feel useless. At that moment, Leopold remembers the strange feeling he felt when he was fighting the elves, and...
I will burn them all to ashes 
with my raging inferno!
!سأحرقهم جميعًا بجحيمي الهائج
Mit dem Inferno in meinen Händen
¡Los abrasaré con mis llamas ardientes!
¡Os abrasaré con mis llamas ardientes!
Je vais tout réduire en cendres
avec mes flammes ardentes !
Le mie fiamme infernali bruceranno ogni cosa, 
e non resterà che cenere!
Vou incinerar todos com
o meu inferno furioso!
Я испепелю всё дотла
своим жарким пламенем!