I'm Just a Wandering Ghost, and You Want Me to Handle the Demon King?

Zhang Xuan transmigrates into a strange world where gods and Buddhas have vanished, and monsters have become divine.

Having become a lonely wandering ghost, he discovers that fulfilling the incense-bearers' final wishes inside the remains of gods and Buddhas lets him inherit their divine offices!

The Mountain God's remains wish for the Demon King to be killed!

Huh?

You want a lonely ghost like me to kill the Demon King?

Zhang Xuan is about to run, but the Wish-Fulfilling System suddenly awakens: as long as the Host agrees to fulfill a wish, they will automatically gain the abilities needed to complete the task!

The Host agrees to fulfill the wish and obtains the Five Thunder Demon-Slaying Seal!

What Demon King? One strike is all it takes!

Fulfill the wish at Stone Mountain, ascend to Mountain God, and rule over three villages and four strongholds!

Fulfill the wish in Qingyun Town, slay the Vajra Blackwind Demon, ascend to Domain God, and rule over three mountains and six lakes!

Fulfill the wish in Thunder City, wipe out the Demon Kings of thirty-six demon lairs, ascend to Divine General, and forge a Heavenly Thunder Dharma Body!

Fulfill the wish in the Northern Domain…

I just keep fulfilling wishes, and now I'm a God King?