So Peaceful Looking.

These are semi-corporeal beings with powerful magical abilities at their disposal. They exist, at least partially, on an alternate and parallel realm of existence known as the Spectral plane, making them difficult to fight using normal physical means. Spectral demons are visually the strangest and most shocking creatures encountered by the survivors of the Burn, and some even have hidden forms that can only be seen by adventurers with a means to peer into their unearthly realm. Their Spectral power sometimes manifests itself in our world as a form of electricity, and attacks based in similar energy spectrums have been found to be highly effective.