"Won't this alert that hidden Demon?"
Shade asked again, but the Doctor shook his head.
"There's no need to worry about that. Vision Demons were the core strength Demon Hunters used against Demons in that dark era, tested by time and several wars. Of course, you must also be very careful. Don't use it too often, and don't use it continuously. Besides, if you're always staring into the void, people might suspect you've gone mad."
Back in the Third Epoch, when Demon Hunters who had made countless sacrifices still existed, the Ring Arcanist system had not yet been established. The Thaumaturgy learning rituals recorded on paper had been altered by generations of Witches and adapted into the Ring Arcanist system. As for the learning ritual for Vision Demons, it was less a ritual than a peculiar potion. Once the potion was prepared and dripped into the eyes, one could gain preliminary control over this Thaumaturgy.
Most of the herbs in the potion's recipe were quite common. For the few that could not be found in Tobesk, the Doctor had also marked places where they could be gathered. Shade only needed to make a trip to Coldwater Port, the cargo distribution center.
The most difficult ingredient to obtain, however, was Demon's Blood. This was not some metaphor or symbol, but actual Demon blood. The Doctor's own blood would not do; he had merely imprisoned some terrifying existence within himself, and he was still human. Fortunately, the Doctor had retained some blood samples from Demons he had hunted in the past for research purposes.
"Besides the inheritance I'm giving you, part of the Third Epoch Demon Hunters' power has already been integrated into the modern Ring Arcanist system. Take the famous Evil Breaking Slash, for example. Its power has been incorporated into