The Immemorial Era had all kinds of intimidating living beings. They all had intelligence and long lives. With giant physiques and earth-shattering power, they were the highest existences in the food chain.
That era was the dawn of the Grace Mainland when earth and heaven energy was still extremely abundant, much more than the so-called level 7 life star. Creatures in Immemorial Era were almost invincible. Legends say that they were even stronger than the ten clans of the next era.
The Immemorial Era had lasted for more than ten thousand years and the immemorial creatures had consumed a lot of earth and heaven energy in Grace Mainland. Eventually, many immemorial creatures had to go to outer space, far away to find more energy.