A rusalka is a sentient, ghost-like being that exists in the world of Thenia. Unlike the rusalka of our world, rusalki in Thenia can be any gender, although a good portion portray themselves as female. Most rusalki haunt waterways, like rivers, ponds, and lakes, but some haunt other areas, most notably forests. A rusalka's main goal is to lure people to their death, either by charm or force, and in some instances, turn their victim into a rusalka like themselves. Rusalki are feared throughout Thenia, as rusalki can be both destructive and violent. Hundreds of death a year are attributed to rusalki, although every Thenian is told of their danger, often by their parents as bedtime stories. Rusalki are created either by another rusalki or through the circumstances of their death: they perceive their death (or a life event) as wrongful and seek revenge. Why some become rusalki when others don't is unknown. However, it is an oft-told warning to children to not become vengeful, lest they die and become a rusalka.
Rusalki maintain much of the same appearance they had as human: however, they often maintain an almost ghost-like appearance, with pallid skin and dark shadows underneath their eyes. Often, female rusalki have long, tangled hair, but maintain a beautiful, youthful appearance in order to lure their victims (male rusalki do the same). It's been said that rusalki can change appearance at will, but that has not been proven yet.
Genetics and Reproduction
Rusalki are not alive, so they are unable to reproduce. However, they can make more rusalki; how this is done is not known to Thenians. Rusalki often do not choose to do this, and the circumstances in which they decide to produce another rusalka is not known.
Dietary Needs and Habits
As rusalki are not alive, they do not require food or any other sustenance.
Rusalki, by nature, tend to be equal parts violent, aggressive, and charming: they require the charm to lure their victims to their deaths, but are vengeful of what happened to them as humans (whatever that may be), and so seek to punish humans for their perceived wrongdoings. To that end, their aggression causes them to act irrationally and dangerously.
Rusalki have little social structure, although it seems that some rusalki have more power than others, thus making them the "leader" of whatever area they're in (several rusalki can haunt an area). Other than that, there is not social structure.
Uses, Products & Exploitation
Rusalki have, in the past, been used a method for revenge: a rusalka makes contact with someone who is angry like them (and that they perceive have a reason for that anger) and then allow them to lure a victim to be killed (although sometimes the vengeful is killed as well). There's also supposedly a spell that allows rusalki to be bound to a magician or witch to do that bidding, but if that's true, the spell has been lost to time.
Geographic Origin and Distribution
Rusalka exist all over Thenia, although they are confined to the area they haunt. Almost all rusalki haunt water, but some are able to haunt other areas, although why is unknown.
Rusalka maintain the intelligence they had as a human, and as most have been around for centuries, their knowledge of the world around them is great.
Perception and Sensory Capabilities
As a rusalka, the beings have a myriad of powers. Rusalka have supernatural senses, as well as strength and speed. Although they are most often corporeal, rusalki have the ability to pass through solid objects and travel at a great speed, almost seeming to teleport. Rusalki also have their own rudimentary magic, and it's said if a magician or witch is made a rusalki, they will be incredibly powerful.
This article is part of my Spooktober 2022 collection! As such, it's minimally edited, and I'll add more when time allows. Forgive the contstruction dust! For those of you that aren't mythology nerds like me, rusalka are ripped straight from our own world's rusalka, but I changed some things to fit this world. Take a read; it's really interesting!