Great Wilderness' Modern Envoy

Modern college student Liam Wilder transmigrates to a primitive world. He is regarded as a Doom Bringer and Demon by the local tribe after lighting a match. Using modern knowledge, he breaks taboos, teaching the tribe to start fires, smelt iron, farm, and treat plagues. Against obstruction from Kai Stone's conservative faction, he rises, leading the tribe to repel invaders, unify the Great Wilderness, become its ruler, and guide clans into agricultural civilization.