Source: Alien Archive, pg(s). 46-47
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An elemental is a creature which is made up completely of one of the four elements of air, earth, fire or water. This means that they do not have anatomies and nervous systems. As a result they cannot be stunned, poisoned or paralysed, and do not have a blind side or vulnerable areas that can be targeted by their enemies. They do not breathe, eat or sleep, and most hail from one of the Elemental Planes.