All magic creatures a by-product - chaos.
Unlike what is claimed by Myth of the Bond, Kondo felt that all magic and technology needed to end and that having an AI run things in the form of the Stone King was tantamount to giving up on humanity. He used both magic and technology to create the Cargothen. He used this device to destroy the world, so he and a small band of followers he protected from its effects could remake the world without magic or tech.
The Stone King believed that using a Toegone - a crystal which collects the chaos released when magic is performed allowed for its safe use and that tech could be employed to save the planet as easily as destroy it. But Kondo wanted power and to destroy him and all other AI at any cost.
There are certain magic users, very rare, that can tame the chaos and use it to enhance their magical abilities. This chaos can be channeled through various materials, that the channeling burns through like fuel as its turned from chaos to magic directed by will, to some extent.
The known materials are blood, Apoplex and your own soul. There are those that say you can use the ancient gods to channel the chaos but that they will demand things in return.