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...
They ended up facing an intensely fiery 
mana unlike any they faced before
انتهى بهم الأمر بمواجهة مانا عنيفة 
للغاية لم يواجهوا مثلها من قبل
Auf dem Weg zum Onsen war das Mana
Allí han de soportar un maná ardiente
peor que el de la superficie
Allí deben soportar un maná ardiente
peor que el de la superficie
Asta et ses amis tentent ainsi
de gagner les sources souterraines
A separarli dal loro obiettivo,
 la sorgente termale nei Cunicoli,
Eles acabam enfrentando uma mana intensamente
ardente, diferente de tudo que já viram antes
Поэтому Аста с ребятами
идут к цели, горячему источнику,