Purple Lotus

Before man and beast learned to absorb atmospheric coherent energy, plants had been doing it for several millennia.

Mutated plants, as such plant species were known, could exhibit a wide range of effects... From wondrous herbal abilities to dangerous poisonous effects, it all depended on the conditions of their environment and the concentration of magic energy they absorbed.

While some could heal injuries, enhance magical abilities, and provide sustenance, others also produced harmful toxins that could lead to illness, affliction, or even death when ingested, inhaled, or touched.

The purple lotus was one such kind of mutant plant. Although the flower was generally harmless to humans, when ingested by magic beasts, it served a whole other purpose:

Due to factors like species and bloodline, it was common knowledge that from the moment they were born, all magic beasts had a predetermined maximum evolution rank they could reach.