A modern man named Li is transported to a primitive otherworld. As soon as he lands, he is carried back to the Giant Ear Tribe by Aura, a 3-meter-tall beast-eared maiden who mistakes him for a "small-eared, hairless male". "Lie", the tribe's successor shaman, is convinced he is the prophesied figure who can save the tribe, and begs him to become Chieftain. Dahla, the strongest warrior, strongly objects, arguing that this male "as short as an unweaned cub" is completely unqualified. When Thief Bird attacks the camp, the beast-eared maidens fight back with their bare hands in chaos. Li uses vines and stones to make a meteor cord and shoots it down, activating the System: he can absorb energy and grow taller and stronger by touching prey corpses. With the knowledge he accumulated from nine years of compulsory education, he leads the tribe to thrive: he invents fire-by-drilling to end the era of eating raw meat, makes carbonized spears and bows and arrows to upgrade hunting, refines salt mines and fires pottery to improve living conditions, tames a Tyrannosaurus rex as a mount, builds giant stone walls, smelts iron to arm the entire tribe. Every technological innovation makes his height and strength surge dramatically.
