Aboleth

The aboleth is an aquatic aberration from the roleplaying game Dungeons & Dragons. These sinister creatures have been a part of the game since its first edition.

Overview
Aboleths are fish-like amphibious creatures that reside in the murky depths of the Underdark and the bleak waters of the Far Realms. They resemble bizarre eels, having long bodies between twenty and forty feet in length. Their skin is typically a sickly shade of green with an orange-pink underbelly. They have three blood-red eyes and have a multitude of tentacles just past the head. While not always visible, aboleths also have horrific circular maws like that of a lamprey, lined with many terrible fangs.

Aboleth bodies constantly exude a slimy grey mucous which they require to breathe. They have four pulsating organs along their bodies that produce and secrete this slime. If robbed of their ability to produce slime, aboleths will suffocate, whether in water or on dry land. Out of water, an aboleth's membrane-like skin will quickly dry up, though this does not mean death in and of itself. Instead, the aboleth will eventually enter a state of suspended animation, called long dreaming, a fate considered far worse than simply dying amongst aboleths. During this process the so-hampered aboleth forms a tough, waterproof membrane. However, if this membrane is pierced, liquid floods out and death is usually not far off for the aboleth.

Abilities

 * Telepathy - Aboleths possess tremendous psionic abilities and use such powers to bend lesser beings to their will.
 * Transformation - The aboleth's mucous has a terrible transformation effect on land-dwelling creatures. The skin of the victim is transformed into a membrane which allows it to breathe in water, and changes the creatures consciousness to that of a mindless servant's. This allows aboleths to keep slaves known as aboleth servitors or skum, which they dominate and keep captive through their mind. Only the most powerful aboleths can do this, however, completing the process through a powerful ritual.
 * Immortality - Aboleths are only immortal in a biological sense. They do not succumb to age or disease but can be killed via unnatural means.