Star Tier was as far as the mortal realm would allow. It was a solid fact and only with a restriction or some other way to make a cultivation reduced to an acceptable level was what allowed those 3 Moon Tiers and Sun Tier from Babylon Guild visit him.
Such artifacts and techniques were not only rare but usually highly resource intensive. Once used, they would maximize their benefits because they could not do it again.
At least, that had been what Owen told Lind.
The man had to leave before the Moon Tiers because the pressure restricting his cultivation used up his artifact much faster. Before the second competition had come round, all of them had returned to the Heaven Realm.
Azylea and Huo followed not long after when they ascended to Moon Tier.