A Demon Hunter by Inheritance, I Took Out a God from the Start

This is the story of two brothers who exorcise ghosts, subdue demons, vanquish fiends, slay immortals, and kill gods to safeguard the peace of humankind! Born with divine strength and inheriting the 36-character God-Smiting Spell, Jiang Nan traveled across the country with his father from childhood, working as a folk monster hunter. After his father died of illness, Jiang Nan went to the Amazon rainforest to clear his head by battling a giant python. Suddenly, his younger brother Jiang Bei, who had possessed the Heavenly Eye since childhood, found him and said that some kind of thing had killed his girlfriend. Jiang Nan then returned home with his brother to take revenge. Who knew the murderer would turn out to be an immortal...