Thirteen Pillars of Human Race

This is a world where thousands of races are fighting against each other, and it also seems like a world where everything has been arranged. But has it really been arranged? A man from the next era returned to this era that did not belong to the human race from the era when the human race was about to die. He led the human race to rise, but in the process of rising, he unintentionally discovered the real secret of the world. But is that the real secret? Or maybe some irresistible factor forced this so-called secret to go from being an ancestor praised and praised by all races from a few transcendent worlds that suppressed the world, to a secret that is now destroyed by the thoughts of all races. How did a boy who didn't belong to this era discover this secret?