When the blockade on the Sky Martial Star was lifted, not only did a large number of warriors from other star domains enter, but many natives of the Sky Martial Star, whose ancestors had left to avoid the decline of martial arts brought about by the cosmic blockade, returned as well.
For an ordinary person, millions of years would mean countless deaths, but for the King of Stars, a lifespan of a million years was natural. With the addition of life-extending Spiritual Medicine, living another hundred thousand or two hundred thousand years was not unusual.
What's more, such powerful beings could enter a state similar to hibernation, significantly reducing life's wear and tear, easily surviving the millennia.
No one could resist the allure of the Immortal Emperor's legacy.
Therefore, the most dangerous ones would be the original warriors from the Sky Martial Star who were from outside the domain because they were also very familiar with Sky Martial Star.