Ebon Dryads

Secondary villains in the Ebon Heart adventure of the Companions of the Rising Sun, they nonetheless caused the death of Perrin Forester when one of their sleep spells caught him, and he was unattended. The subsequent beheading spelled his doom in short order.
Capable of blinking around the battlefield and disguised by their resemblance to grave marker angels, they proved to be a deadly foe. Two of them were slain, one captured and redeemed with the destruction of the Ebon Heart itself.