There are 14 books in The Wheel of Time series, plus a prequel. They came out between 1990 and 2013. That's 23 years, ...

Thus, I dusted off my Scandinavian heritage and did significant study of the Poetic Edda and more specifically the Völuspa (The Seeress Prophecy) and wrote the text for Ragnarök (Destiny of the Gods).