The answer to the question of how much money could be earned by writing a fantasy novel with 50 million words depended on many factors such as the quality of the novel, its popularity, publication, and publicity. A good fantasy novel could be very popular and even become a bestseller, bringing huge economic benefits. But even a very successful novel may not be very profitable because the market for fantasy novels is relatively small and the competition is fierce. Besides the quality and popularity of the novel, publication and publicity were also factors that affected the profit of the novel. If the novel was published and received good reviews, it might be necessary to pay a copyright fee. If the novel was promoted and became popular, then they might have to pay copyright fees, advertising fees, and other promotional fees. Therefore, the profit from writing a 50 million word fantasy novel could be very high or very low, depending on many factors.