They have seldom if ever seen daylight and often exist in total darkness unless another species brings light. Nideans see extremely well in low lighting conditions. Nideans are rarely seen ashore but it does happen at night, when they venture onto land in search of materials they might need, including fruits, which they consider a delicacy. Nidean songs are sometimes heard deep underground and are one of the earliest signs of their presence, though the music appears to be coming from everywhere.
They and other life forms in their habitat are often bioluminescent. They tend to be shorter than humans; some think they are mandean children. Their skin is often pale, even translucent so that internal organs are visible. Nideans wear nothing
Nideans exclusively live in deep underground rivers and, more commonly lakes. Rivers are used for hunting and travel. They are indifferent to climate, but on the rare occasions when they venture outside, it is virtually always at night. Nideans have such a small area to live in that they don’t have actual settlements. There’s never been a nidean in a joint settlement unless it was captured.
Nideans don’t have any formal schooling. Therefore, wizards don’t exist, only sorcerers, but they see little reason to use such talentsexcept for protecting their people, often by disguising them, hiding them, or making it hard for anyone but nideans to locate them
Nidean populations are always small due to habitat. Diversifying the gene pool is one reason they’ll go on land, to find another population by entering another river nearby. They can seldom speak Antarian (common) and only know the finger language (Mandean Hand) and their own dialect of mandean.
Nideans never fight anything, just running away. They have no weapons other than their teeth and claws. They don’t even use spears to catch fish for themselves.