Isaac and the Black Sword Knights are responsible for training the Maihama army. While he's in Maihama Isaac gets to know the new crown prince of Maihama, a young boy named Iselus.  Iselus respect looks up to Isaac and respects him.
At a party for the crown prince's birthday, assassin's make an attempt on his life.
You're better at judging swords 
than I am, aren't you?
Aber du kennst dich doch besser
mit Schwertern aus, Bruder Isaac.
Tú eres mejor juzgando 
las espadas que yo, ¿no?
C’est toi, l’expert en épées.
Sei più bravo di me
 a giudicare le spade, o sbaglio?
Você é melhor para escolher
 espadas do que eu, não é?
Но в мечах разбираешься
у нас ты, дорогой Айзек.