Novel starts when ML, the chief of a tribe who doesn't have a wizard/witch went to look for MC to ask him help to cure his people from the plague. MC readily agreed and in fact already prepared the medicine. MC generously imparts knowledge(making medicine, glass, steel, etc.) to the tribe and is satisfied about the strong independence of the tribe compared to other tribes that rely heavily on the wizard/witch. MC made a little dragon which later became the tribe's beast god. MC found 2 pets a giant bird and a giant ape which later helped them in hunting prey. MC later visited various tribes and named the beast gods ancient mythical names which they liked compared to what their tribe called them. MC somehow entered a special realm where he talked to the world consciousness and told that it summoned him to this world to bring change. MC eventually unified the surrounding tribes (not including tribes/countries across the sea) and by the end of the novel it reach the interstellar where one of the wizards reincarnated with memories and is constantly troubled by MC without memory. MC and ML can actually choose to live with their previous life memory but MC prefer to live their new life as a new person.
Is this a novel you saw on NU? or read somewhere else? because I've not seen a novel like this at all. It does sound intriguing and I would like to know more details. can you remember the name of the MC or the ML??