Apollo, one of the 12 Olympian (major) gods of Greek mythology, is the protagonist of the novel. The god of the sun, music, poetry, and healing, Apollo appears as 16-year-old human teenager Lester in the Trials of Apollo series. The dichotomy between Apollo and Lester gives Apollo’s character depth and complexity. In his human form, Apollo remembers his life as a god, but he has lost most of his supernatural powers as well as his perfect, immortal form. Apollo feels punished by the transformation because humanity to him signifies weakness and mortality. As the series progresses, Apollo begins to appreciate human emotions and experiences such as regret, sacrifice, humility, and friendship, which make him more empathetic. Apollo begins to settle into his Lester-self, realizing that there is much more to being a mortal than he had assumed.

Because Apollo goes through a gamut of emotions and perspectives, his character arc is evolving and his character is dynamic. In The Tower of Nero, Apollo is closer than ever to seeing human existence as a gift, rather than a punishment. Ironically, as he realizes this, he inches closer to regaining the godly powers and immortality he has been chasing since the first book of the series.