As previously stated, Yaoin are either lithotrophic or a decomposer bacteria.
Lithotrophic Yaoin take their nutrition from the water of Daomhaen. They absorb minerals and nutrients using a thin, sticky membrane which wraps around particles that are caught onto it. They are then usually absorbed.
However, particles such as silicon or metal waste from Laoine contribute to a shell that is on the outside of the creature. This provides minimal protection from predators and the environment.
Decomposer Yaoin are usually larger than lithotrophic Yaoin. This is because they need to live in larger groups to decompose dead creatures (Raeraen and other meaty creatures) quickly to avoid being eaten. They also tend to eat each other, mainly out of accidental absorbance.
Laoine sometimes use these in medicine, because their decomposer properties allow them to cure cancer-like growths that are considered to be 'dead,' but cause other cells to die. There are currently no other treatments -except all-out amputation- so Laoine tend to artificially accelerate their development and growth.
Yaoin tend to live in groups of several thousand to a few million. They do not share a hive mind, but just stick together for survival purposes unknowingly. This survival method has been an illusive topic to research because they have no sort of intelligence whatsoever, even for the scientific Laoine.