There are 3 books in the Riddle-Master trilogy / Morgon series.
The Riddle-Master trilogy / Morgon series does not have a new book coming out soon. The latest book, Harpist in the Wind (Book 3), was published in January 1979.
The first book in the Riddle-Master trilogy / Morgon series, The Riddle-Master of Hed, was published in August 1976.
The Riddle-Master trilogy / Morgon series primarily falls into the Fantasy genre.