Nightblood is the working title for the sequel to Warbreaker. It is currently on hold, and probably the cosmere book most in jeopardy of not being written.
"Elantris and Warbreaker sequels aren’t to be expected until Stormlight Five and Wax and Wayne Four are done. Status: Keep waiting. (Sorry again, again.)" - Brandon Sanderson (2019)
Details updated August 8, 2022
Brandon Sanderson was born in December 1975 in Lincoln, Nebraska. As a child Brandon enjoyed reading, but he lost interest in the types of titles often suggested for him, and by junior high he never cracked a book if he could help it. This all changed in eighth grade when an astute teacher, Mrs. Reader, gave Brandon Dragonsbane by Barbara Hambly. Brandon thoroughly enjoyed this book, and went in search of anything similar. He discovered such authors as Robert Jordan, Melanie Rawn, David Eddings, Anne McCaffrey, and Orson Scott Card. Brandon continued to be an avid reader through junior high and high school. He liked epic fantasy so much that he even tried his hand at writing some. His first attempts, he says, were dreadful.