Kevin Hearne's
Iron Druid Chronicles series is fantasy featuring a 2,000 year old Druid.
https://www.goodreads.com/series/528...uid-chronicles
Ken Grimwood's
Replay is about a man who dies at 43 and wakes up in his 18 year old body and continues to
replay over and over. Personally, I don't consider this science fiction/fantasy but over 2/3 of Goodreads people tag it that way. An interesting book regardless.
https://www.goodreads.com/book/show/...m_search=true#