Ciri, the Child of Destiny, wants to leave, but she’s being hunted by friend and foe alike. who are looking for her, for different reasons in different timeline
The hard science parts are certainly ambitious. The author goes into such topis as oceanic physics, as well as science of the atmosphere
This is not part of an epic saga which is a staple in the world of fantasy. Geralt rides the countryside, meeting people, talking to them, and killing a monster