Twilight of the Kai
“Darklord Vashna originally bred the Helghast for the wars against the Sommlending. They are powerful, undead creatures who can adopt human form at will. This, coupled with their invulnerability to normal weapons, makes them ideally suited to missions of spying and assassination. They have greatly furthered the Darklord cause by the subversion of countries in Northern and Southern Magnamund.
“There remains no foolproof method for detecting Helghast amongst our midst. Those of you with well-honed psychic senses may feel their wicked presence, but this is not always reliable. Often, the first indication of a Helghast nearby is an ear-splitting shriek and the flash of black steel. And unless you possess an enchanted weapon, you have no hope of defeating them. There is no shame in running and regrouping if you may do so without the further loss of life. Otherwise, prepare to sell yours dearly that others may flee.”