Ethereal marauder

An ethereal marauder was a predatory monster from the Ethereal Plane. Nilshai, sorcerers of that plane, were said to keep ethereal marauders as guardians.

Description
Marauders resemble blue or purple two-legged lizards with long, flexible tails. Having no neck to speak of, their massive mouth with its three mandibles was attached directly to the creature's body. The mouth was lined with black teeth. Between each pair of mandibles were one of its three tiny eyes.

Marauders stood about four feet (120 centimeters) tall and tended to be seven feet (210 centimeters) long, but some specimens could be double that size. They weighed a couple hundred pounds (90 kilograms) on average.

Behavior
The native behavior of ethereal marauders on their home plane was not well-known. Their forays into the Prime Material Plane occurred when they were hunting prey. They had no society or culture but behaved more similarly to natural wild animals.

Survivors of their attacks claimed that they made an "eerie whine," which varied in pitch depending on the monster's speed and condition

Combat
Marauders had the magical ability to shift from the Ethereal Plane to the Material Plane and back again, much like the ethereal jaunt spell enabled a spellcaster to do. They would use this innate ability to ambush prey, snapping into existence, biting with their razor teeth, and retreating into etherealness.

They usually hunted alone.

History
In 1372 DR, the famous ranger Drizzt Do'Urden and his companions were attacked by a rare cluster of overgrown ethereal marauders, while investigating the ruins of the dwarven and Orcish town of Baffenburg. Whatever catastrophe destroyed the town was thought to have weakened the planar barriers between the Material and Ethereal Planes, which was why the marauders were roaming there.