Miasma
Miasma (瘴気) is a physical substance, a gaseous compound produced by Talyxian organisms that contain mind-altering properties with the Eltus.
The Miasma occupies parts of the Northern and Eastern lands. While there are differences in nature and function between Northern and Eastern miasma, all miasma is considered to give some sort of negative effects on Eltus. Regardless, Eltus people require special equipment such as a gas mask to ensure their senses and sanity are in check.
Northern Miasma
Some parts of Northern primeval Talyxian forests are filled with strong miasma from the distant past. It is said that it affects people's brains over a long period of time. As its effect, as can be seen in primitive Northern Sergals' behavior, it's said that hinders people to have a strong will and thinking faculty of their own. As a result, it makes people have adapted to their own near insanity and aberrant situation.
The Miasma is not a rapid process, but one that takes time. Its influence on a given person will change their mental condition little by little, the more they are exposed.
Eastern Miasma
The detailed information is still pending.
The Miasma occupying the Eastern lands such as the Magoe forests is much stronger than its Northern counterpart. In order to avoid the absorption of miasma, Eastern people have developed gas masks and these technologies.
Common Term "Miasma"
Miasma is not a perfectly fictional term that is specific to the Vilous Universe. The same term had been used in superseded theories in the real world, Miasma theory.
In ancient times on Earth, Miasma was originally believed to cause the distribution of diseases, such as the black death, a theory that has long since been abandoned.
On the Planet Tal, while the Miasma shares a concept "a gas that gives negative effects on people" it also owns mysterious effects that affect the mind with some kind of interaction with the Talyxian environments.