Thread:Auric Drake/@comment-36876768-20190321152324/@comment-34962159-20190322095921

Rereading the Volume 17 Prologue, that specifically says:

"The Arcadia Empire that accepted the Xfer clan in the past of more than a millennium ago climbed to the top with the power of the Ruins and reigned there, but at the same time it stepped onto the path towards destruction.

The influential people who obtained achievements at the beginning eventually turned their fangs toward their compatriots who were in weaker position.

──Elixir.

It was proved that the optimum raw materials for the secret medicine that awakened the sleeping potential of humans and strengthened them were humans with a close blood relationship. Since then the exploitation of life itself began."

Basically, the higher-ranking members of the royal family used the lower-ranking members as materials to make Elixir. The Xfer were not involved.