Nightwraiths - The Witcher 3

Nightwraiths exude this immense sadness, this helpless wrath… I fear them, same as anyone. But most of all I feel sorry for them.
– Aelline Altsparr, elven trobairitz.

Compared to other creatures of the night – katakans, nekurats and werewolves, for example – nightwraiths (and their rarer cousins, duskwraiths) might not seem all that dangerous. After all, one might ask, how much harm could a pale, withered woman in a tattered dress do? The answer: quite a bit. Instead of finding this out the hard way, avoid crossing fields and meadows at night at all costs.

Like noonwraiths, nightwraiths are only found in rural areas. Travelers fall victim to them most often, but if legends are to be believed they also sneak into huts at times and murder peasants in their sleep.

When they attack nightwraiths remain immaterial for most of the time, meaning physical blows pass right through them. They only take on more tangible form for the brief moments in which they strike. When weakened, they will create several projections of themselves which cannot attack directly but act as transmitters of sorts through which the nightwraith can sap her victim's vital energy.

Nightwraiths can turn immaterial and are at such times very difficult to wound. In order to force one to take on corporeal form, trap it with the Yrden Sign or hit it with the blast of a Moon Dust bomb.

Do not believe the old wife tales and think yourself completely safe from nightwraiths during the day. They appear under the light of the sun as well - but are much weaker then than after dusk.