Only one month remained for the promised fight. For the last couple of weeks, Ariha had been training him personally... Well, she was doing that from the beginning, but after the heart transplant, she had become more involved in teaching him.
Most of it related to how he wielded the Radiance essence. She was a master in it, and he wouldn't find anyone better to teach him all about it.
Honestly, half of it was intrinsic, and as his body adapted to the change, his recovery power went beyond absurd levels. She also taught him a few Radiance spells, which used ancient runes he hadn't known yet.
Ariha was reluctant to teach any healing-related skills. She demonstrated two common spells related to healing and rejuvenation and was done with it. He wanted to learn more of them, but considering the circumstances, he didn't blame her.