Because of this, Martial Arts Association and Magic Association made announcement almost immediately.
They shared the method to prevent their magic cores from being taken by the demonic magicians.
There were so many of them.
And these have been proved to be effective by them.
As for how they knew so much…
Samuel and Ruth shared their knowledge about this matter a long time ago. This was because when they found out that Dina Alden is in this world, they have long prepared countermeasure to deal with her.
None of them would allow Dina Alden to take their mana cores.
Dina herself also knew that even if she wanted to take other humans' magic core or often called as mana heart, she could not target the other returnees like her. Because each and every single one of them definitely have terrifying methods that she might not be able to bear.
For the sake of her own life, Dina should not target them.
