Transmigrated to the Cultivation Realm, I Gain Immortality Through the Sign-In System

Chen An arrives in the cultivation world as a good-for-nothing and thinks he'll be able to lie flat like this. But then he binds himself to a sign-in System. At first, all he can sign in for are common herbs and cultivation techniques, until he unexpectedly discovers that signing in near anyone at the Golden Core stage or above can yield rare items.