When had Anton come up with "Magic Enhancement"? That had been a long time ago.
Back then, he had taken his friends from the little cottage to Werewolf Home to lift the Werewolf Venom curse from the werewolf wizards Lupin was protecting. He had come up with the spell while he was at it. (Chapter 670)
With that magic, Anton had raised his friends' strength by a whole level for the first time.
He had made many "bodies" for his friends.
Hannah, in particular, had acquired the magical bloodline of Garden Gnomes in Hufflepuff's Chamber of Secrets. As a result, she had gradually become unable to cast ordinary magic, much like Lockhart.
This ritual magic had solved that problem, too.
Of course, that had been the earliest version of Bloodline Stacking Ritual Magic. As Anton's research had advanced, especially in the field of Gray Magic, he had naturally made further improvements to the ritual.
Instead of stacking the bloodlines of Fantastic Beasts, it now stacked one's own bloodline.
Or perhaps it was more accurate to say that it indirectly stacked one's magical bloodline. Anton's research had always moved from the soul toward the magical bloodline, rather than from the body.
That was the foundation his mentor Fiennes had laid for him, bit by bit, with the teaching that "a wizard is a god." It was also the foundation his Potions professor Snape had built by personally teaching him about "the relationship between the soul and bloodlines."
The strongest part of one's mind might be a memory, an intense emotion, an indomitable will, a particular period in one's life, or the most unique mark one had left on this world...
Using Gray Magic, this part of oneself was joined with the magic of the collective consciousness. That nourished the Dark magic