"Poisons are really interesting," Kadyn murmured as he read the book while sitting on the counter, waiting for customers. After realizing that he had no affinity with Formations, he stopped learning about them and focused on learning about herbs—and poisons also come in the same category, so he also learned about them, and the more he learned the more interested he became.
There was a method inside the library that would let one develop Poisonous Mana Pool. That really caught his attention. After developing the Mana Pool they needed Spell Glyphs to cast their spells, but other than that—they also needed to concoct poisons and then merge them with their Mana Pool, and to cast a spell required Spell Glyph together with specific poison.
Poison Masters had the same ranking as other mages, like—only Rank 2 Poison Master or above could merge Rank 2 poisons. If your rank was lower than a poison, death would be mercy for you.