Book Two of the Astra Windlass trilogy.
After the conflict with Kronos and learning about Ouranos' attempt of resurrection, Astra Windlass, daughter of Artemis, is sent on a mission. The Aphrodite cabin has gone missing during their trip to Olympus, and so has the goddess herself. On the other hand, random fights have abnormally been breaking out among campers in Camp Half-Blood, and it's up to Astra and the gang to figure out what's up. Alongside these mysteries, an unexpected reveal from one of the gang's family members will have everything succumb into chaos.
Even with the feud between Astra and her grandfather, she goes on the quest in hopes of figuring out who exactly is behind all of this. Who is causing the discord in the camp? Does the rising of Ouranos have something to do with this? Or is Astra possibly overthinking everything and should probably settle down with a chocolate taco?
Based off the Percy Jackson and Heroes of Olympus series [written before ToA].