He Who Shatters the Divine Order

"After awakening a useless dark serpent, Wayne Yeager is cast out by his fiancée and sect. Bound by a blood pact, he rises through devouring and evolution. Along his harsh journey, he meets a sword immortal and a strange, ugly bird, surviving deadly realms and battles. Betrayed by the hypocrisy of the immortal world, he fuses with the serpent, becomes the sovereign, shatters the heavens, and rewrites his fate.