When Starry Sky and Ash condensed their Supreme Tail Feathers, they knew their tail feathers were not complete.
They had split the Supreme Holy Grail equally, so the Source Angel's authority had naturally been divided in two. But even with only half the authority, it was enough for each of them to condense a Supreme Tail Feather, because condensing a Supreme Tail Feather only required you to possess more than a certain number of seven-wing feathers.
Arcanists like Vishy, as well as the other God Lords, also had a chance of condensing the Seventh Void Wing.
But while the Supreme Tail Feather had a lower limit, it had no upper limit.
Unlike the Silver and Gold Void Wings, which had an upper limit, the Supreme Tail Feather was a Void Wing that could be stacked infinitely. If Starry Sky obtained the complete Holy Grail, then right now she could condense a Seventh Void Wing with twice the authority.
Besides that, the Seventh Void Wing had another extremely important trait: it had an ultimate upper limit.
Simply put, the total amount of Supreme Authority in the entire world was fixed, so the number of arcanists who could condense the Seventh Void Wing was naturally limited.
If you ate more, others ate less. More importantly, there was no way to increase the total amount of Supreme Authority through means like the development of civilization.
One had to know that the Sixth Void Wing had a similar restriction, because the total number of World Secret Domains was limited. Without a World Secret Domain, an arcanist could possess an enormous Heaven and still not be a Six-Winged God Lord. But as civilization developed, the Void Realm's World Secret Domains would gradually increase. For instance, the Wishing Pool belonged to the World Secret Domains that