Yuyui had remembered it clearly. After all, her master had mentioned it just hours ago, after he had ascended and before everyone left for their respective missions.
"My possessed self was a tough, ruthless bastard. I learned a few things from him that I probably would never have realised," Skullius said to the Stark Troops. "For instance, with the right number of Creeds, you can enhance an already active Territory. You just call its name again, pay the cost, and it becomes much stronger. Or, you could do it again, again, and again as you see fit. Luckily for the Incandescent Stagers, the Impossible Task earned you all a lot more Creeds than you could ever use at once, so go crazy."
(A/N: Refer to Ch.1216.)
And indeed. In addition to levelling through Tasks and Trials, Creeds could be earned by performing god-like feats. (In fact, this was the fastest and most efficient way to earn them.)