I'm a Lonely Ghost, You Want Me to Take Down the Demon King?

Zhang Xuan travels through a strange world where gods and Buddhas disappear and monsters become gods. He became a lonely ghost, but found out that by fulfilling the last wish of incense in the remains of gods and Buddhas, he could inherit their priesthood! The last wish of the mountain god's remains is to kill the demon king! Kindness? Let me, a lonely ghost, kill the demon king? Zhang Xuan wanted to run away, but the wish-making system suddenly awakened: as long as he agrees to make a wish, the host will automatically gain the corresponding ability to complete the wish-making task! The host promised to fulfill his wish and obtained the Five Thunder Demon-Slaying Seal! What kind of demon king? Kill with one blow! Shishan fulfills his wish, becomes a mountain god, and rules three villages and four villages! Qingyun Town fulfills its wish, slays the black wind demon of Vajra, is promoted to a domain god, and rules three mountains and six lakes! Leicheng fulfilled his wish, defeated the thirty-six demon kings in the demon cave, was promoted to a divine general, and condensed the Heavenly Thunder Dharma Body! Northern Territory still wishes...... Still alive, still alive, I have become the God King?