From publisher blurb:
In Blade of Fire, a group of level-5 adventurers learns about the story of Glen Kyte, a man who lost everything to an order he once served. The Knights of Light are his lifetime-sworn enemies. After years of gaining power and wealth, Glen learns about a legendary sword that might change his stars. The stories claim that the fabled Blade of Fire grants godlike power. With it, the former knight has a chance to fulfill his hateful vendetta.
Glen has committed atrocities to accomplish his goals and killed innocents to learn the whereabouts of the sword. It is too late when Glen is confronted. The Blade of Fire has taken hold of him. A formidable foe, capable of burning entire villages, is what remains of the disgruntled human. Will someone stop the Avatar of the Blade?