For some reason, Captain Yami tells all the Black Bulls to take a bath with him. After not being able to fight with Yuno in the Royal Knights Selection Exam finals, Asta had been acting like his soul was gone. While in the bath, Yami starts to tell the Black Bulls about an incident that happened when he had just become a Magic Knight and had gone on a journey to train.
As for the mysterious mage who called himself 
Xerx, we found out his real name was...
أمّا بخصوص الساحر الغامض الذي لقّب نفسه 
...زاركس ،فقد اكتشفنا بأنّ اسمه الحقيقيّ هو
El misterioso mago que se hacía
llamar Xerx era en realidad…
El misterioso mago que se hacía
llamar Xerx era en realidad…
Il mago misterioso che si faceva chiamare Xerx, invece, 
si è scoperto rispondere al nome di...
Quanto ao misterioso mago que se chamava Xerx,
descobrimos que seu verdadeiro nome é...