I spent some time talking with Leianne before we went out to check on the corpses of both Transcendents and Mortal Ranks who all died at the same time.
According to what Leianne learned from one of them, the Dark Wizards, or what they called the tribe who's leading the invasion in this world, had the method to exploit the Magical Energy. They used that method to create these Transcendents.
As to how they passed their Transcendent Trials in this world, it's still a mystery.
We didn't have any contact with the World's Will of this world yet.
Is it not active? Is it ignoring our existence or has it given up already?
Considering these pawns of the Dark World managed to reach Transcendence, it probably gave up.
If I recall correctly, Hiroda was always forcefully summoned because of the looming crisis in this world…
Could it be they're now in hiding? If not then this world should've been conquered long ago.
