Black Iron and Frost

On the northern border, Leon, the sixteen-year-old son of Orion, took over the black iron badge left by his father and embarked on the journey south. There is no magic, no blood, only a hunting knife and the words "survive". From the bloody highway to the sewers of the royal capital, from defending an isolated city to an expedition behind enemy lines - when he finally stood at the end of the world and faced the wailing Demon King, he discovered: Killing the Demon King will destroy civilization; replacing the Demon King, he will perish forever. What do mortals rely on to fight against fate? Black iron. And behind the black iron, that undying heart.