Xia Moan, a hardcore base-building and resource management game enthusiast, is summoned by the desperate half-demon Talia Ronoway. He journeys to another world and is unexpectedly possessed by an ancient cursed armor. He builds the most powerful Demon King's city from scratch in the harsh underground demonic realm! What? Building a dungeon is difficult? Here's the "Alien Underground Colony Construction System"! The most advanced technology is indistinguishable from magic, and the most rational science will incorporate magic into its systems! The stage of elven lords, dwarven princes, and demihumans is gradually coming to an end. The struggle of the four kingdoms, the war of kings, the era of humanity has just begun! The world is so big, why not go and see it? The tunnels of the earth-devouring demon worms create an underground ecological maze. The wasteland is the gold mine and burial ground of the Adventurer's League, and the back garden of the demon rulers! Magic stone warriors,...