Jack Williamson 
Power of Blackness [EPUB ebook] 

To win the right to a name, he fought without weapons in the deadly arena of Nggongga — only to be cheated of his prize. Branded a criminal, he sought refuge with the Benefactors, a mysterious interplanetary fellowship, and from them he at last learned the truth about his heritage. As Blacklantern he was born again — and the galaxy itself became the arena for his vengeance. A gladiator still, his purpose took him to the ends of the cosmos, to seek out and finally face a terrifying and relentless evil that threatened countless worlds…