The best of this series so far. Every character has great development, and the stakes are high from the get-go. My obvious favorites are Percy, Annabeth, and Nico (OG series forever) but Leo and Frank really grew on me in this book (I liked Hazel from her introduction, and she only got better). The only weak point in this book for me is that I have a hard time connecting to Jason. Piper's identity has always felt tied to Jason, but she began to individualize in this book and become her own hero. Unfortunately, I feel like that left Jason in a lurch. He's not quite Roman anymore, but he's not Greek either. I think that as a reader, you also aren't sure where you fall with him since he doesn't know where he belongs either.