Mishap!
As they had killed their first magical beast without any trouble, Ark decided that it was probably for the better if they kept training for a little longer, preferably against something stronger. Ephine hadn't even gotten her chance to fight yet, and he wanted them both to experience how it felt to fight in these new bodies. For the majority of the time, they would all still be wolves, but for the times when they were not, they needed to be ready to fight and protect themselves, as Ark couldn't protect them forever.