2nd Ed. Monstrous Manual said:They are further condemned to remember their crime in song on any night when the moon is full; few sounds are as terrifying as a death knight's chilling melody echoing through the moonlit countryside. Death knights are likely to attack any creature that interrupts their songs or trespasses in their domains.
Agent Oracle said:Even better Quaziquest: "The empty husk of a Umberhulk" no internal goo, just the re-animated withered shell, like the corpse of a dead bumblebee that's been curled up inside a window frame for a month.