Lin Mo, an ordinary young man who traveled to Douluo Continent, awakened the 'Underworld Sign-in System' and could sign in at various halls of the underworld to obtain rewards such as soul rings, soul bones, and ghost attendants. He signed in at the beginning and received a million-year underworld soul ring, but was mistaken for a useless martial soul because of the strange aura of the soul ring. At Notting College, Lin Mo practiced in a low-key manner, using the underworld sign-ins to continuously obtain artifacts such as the King of Hell's Order and the remaining pages of the Book of Life and Death. When the Wuhun Palace suppressed civilian soul masters on the pretext of hunting soul beasts, Lin Mo summoned an army of ghosts to fight back, exposing his true strength. While signing in to unlock the laws of reincarnation in the underworld, he established the power of the 'underworld palace' and conquered the incarnations of hundred thousand year old soul beasts and hidden masters. In the soul master competition, he used his million-year soul ring to crush the genius and exposed the darkness of Wuhun Palace. In the end, Douluo Continent and the underworld were integrated, and he became the supreme god who controlled life and death, guarding the balance of the world. The core selling point is the integration of the underworld system and the world of Douluo. The target readers are fans of cool literature. The cool path is to pretend to be a pig and eat the tiger, to crush with technology, and to establish power. The core value is protection and revenge.