According to the demonesse, the Holy Ones got tons of tech from the endless races they devastated over the years in many universes.
So it was hard to try and grasp their full knowledge or learn more about them as they'd always got a way to deal with any kind of powerful foes.
This tech released strong waves of energy that were able to take away any strong armies threatening these ten worlds. In addition to that, these waves were able to deal with any energy based attacks.
They reminded me of my pillar's offensive wave skill, and my chariot's pulse wave cannon. But the latter was much smaller compared with that kind of scary attack.
Per her description, the waves emitted from this tech were fierce enough to change the entire layout of the ten worlds.
Thanks to their energy nature, the Holy Ones would never tend to use such a deadly weapon until they were quite sure of the level of threat endangering their worlds.