I think 'Blaze of Glory' is fiction. It could have elements of creativity and imagination that set it apart from real-life accounts or non-fiction works.
It wasn't Dragon 4. It was the name of a character in the novel " Battle Through the Heavens ". Blazing Sky was the name of a character in Douluo Continent.
One great fanfiction is 'A Journey of Hearts' which beautifully explores the relationship between Tsubasa Sakura and Syaoran. It delves deep into their emotions and the challenges they face in a very creative way. The author does an excellent job of capturing their personalities as we know them from the original work.
There were many animes similar to Tsubasa's Chronicles, such as:
"Fate/stay night": This is a Japanese manga and anime story created by Type-Moon. It tells the story of the war between humans and vampires and the story of the protagonist, Emiya Shiro, becoming a Paladin.
2 "Tokyo Saka": This is a Japanese manga and anime story created by the author Tomoya Kaneda. It tells the story of the struggle between humans and Saka, as well as the story of the protagonist, Kimki Ken, growing up.
[3]"The Attacking Giant": This is a Japanese manga and anime story created by Shokuyama. It tells the story of the war between humans and giants, as well as the story of the protagonist Alan's constant growth.
4."Forbidden Magic Book Catalog": This is a Japanese manga and anime story created by Kazuma Kanike. It tells the story of the struggle between humans and magicians, as well as the story of the protagonist, Tama Sujo, constantly searching for the Forbidden Book Catalog.
5 Sword Art Online: This is a Japanese manga and anime story created by Shaft. It tells the story of humans entering the game world through virtual reality technology and the story between the main character Kirito and other characters.
These animes all had fantasy elements similar to Tsubasa's Chronicles.
It's popular because fans are attached to these characters. Tsubasa Sakura and Syaoran have distinct personalities. Fanfiction allows fans to put them in new situations, like facing new enemies or going on unexpected journeys. Also, the fans can add their own twists to their relationship, like how they first confess their love or deal with misunderstandings.
The Tsubasa Chronicles was originally published in Shueisha's comic magazine, Weekly Shōnen Jump. Later, the manga was adapted into animation, novels, and other forms, and it was widely recognized in different media.
Since I'm not sure specifically about 'free blaze novels', generally, free novels might have the characteristic of being accessible to a wide range of readers without cost. This allows more people to discover new authors and stories.