Non-alien Creatures Wiki
Chasme
Naming
Others Fly Demon
Morphology
Body type Insectoid
Average height 7'
Intelligence
Sapience Sapient
Aggressivity Very high
Ecology
Place of origin Abyssal Planes
Diet Hematophagous
Locomotion Hexapodal
Status Least Concern
(listed as "common" in-game)
Behind the Scenes
Universe Dungeons & Dragons
Created by Gary Gygax


Chasme, also known as Fly Demons, are common demons on the Abyssal Planes. Hematophagic bloodsuckers by dietary nature, they hate other species of demon, though they will ally with Rutterkin when necessary; however, they hate this species, too.

Monster Manual descriptions[]

2nd Edition[]

The chasme, or fly demon, is a particularly loathesome monster, resembling a cross between a common fly and a human. It stands on 4 fly-like hind legs and grasps with its forelimbs, which are equipped with strong, chitinous, pincer fingers. Like flies, chasme can walk on walls and ceilings. A chasme has wings and the blue-black, hary body of a fly. The head is humanoid with saucer eyes and a mane of stiff, backswept bristles. The mouth is tiny, but the nose is sharp and horn-like and used to bite and draw blood.

As with all minor demons, chasme have infravision, the ability to cause darkness (within a 5-foot radius), and to teleport. In addition, a chasme can do any of the following, 1 at a time, at will: detect good, detect invisible, telekinese 1500 gp weight. The touch of a chasme will cause fear as a wand. At all times, except when using spell-like powers, a chasme can buzz and drone in a horrid, rasping voice. This sound has a chance (equal to 100% minus 10% per level or hit die of each opponent) of causing opponents to fall into a comatose sleep. This must be checked each round. Sleeping victims must be splashed with water or vigorously stimulated to awaken them. Otherwise, sleep persists for 2-8 hours or until the chasme drains the victim's blood for 1-4 points of damage. Chasme can be struck by normal weapons, but poison does not affect them. If hard pressed, a chasme will attempt to gate in another of its kind (15% chance of success).

While chasme hate most other types of demons, particularly the stupid vrock and hezrou, they are intelligent enough to avoid fighting with other demons unless the chasme have the advantage. Rutterkin are allied with chasme, although chasme are not fond of rutterkin and use them.


Demons in general[]

Each type of demon, and especially the high-level demon lords and princes, have many unusual characteristics and extraordinary abilities.

Demons are able to move from their own plan into those of Tarterus, Hades, or Pandemonium or roam the astral plane. However, they cannot enter the Prime Material Plane without aid (conjuration, gate, name speaking or similar means).

Demons are chaotic and evil; the smarter and stronger rule those of their kind who are weaker and less intelligent. The less intelligent will attack without question and fight until slain. No demon can ever be subdued. All are able to divide their attacks amongst 2 or even 3 opponents if their means allow.

Demons will never willingly serve anyone or anything. If forced to serve through magic or threat they will continually seek a way to slay their master/captor. Those to whom demons show a liking are typically carried off to the demons' plane to become a slave (although a favored one.) Note that demons can be summoned by characters of any alignment, but controlling a demon is another matter entirely. A thaumaturgic circle will serve to keep out lesser demons. A special pentacle is required for greater demons. The threat or reward which the conjuring party uses to attempt gaining a demon's service must be carefully handled by the dungeon master. Demons are repelled by holy (Good) relics or artifacts.

Demons frequently roam the Astral and Ethereal Planes. Their attention is attracted by persons in an ethereal state. If the name of a particularly powerful demon is spoken there is a chance that he will hear and turn his attention to the speaker. A base 5% chance is recommended. Unless prepared to avoid such attention or to control the demon, the character should know that the demon will thereupon immediately kill, by whatever means are most expeditious, the one pronouncing his name.

Demons are affected by these attack forms: acid, full; cold, half; electricity (lightning), half; fire (dragon, magical), half; gas (poisonous, etc.), half; iron weapon, full; magic missile, full; poison, full; silver weapon, none unless affected by normal weapons in which case damage will be according to the weapon type.

Because they have a special form of telepathy, demons are able to understand every intelligent communication. Demons with average or better intelligence are likewise able to converse.

Typical Inhabitants of an Abyssal Layer[]

Although each layer of the Abyss differs from every other and some of these planes change wildly from day to day, the following general types of creatures will be encountered on many of them:

  • Alu-demon - rare
  • Achaierai - common
  • Babau - uncommon
  • Bar-Lgura - uncommon
  • Cambion - very rare
  • Chasme - common
  • Daemon - rare
  • Demodand - very rare
  • Demon Lord/Prince - very, very rare
  • Dretch - common
  • Glabrezu (Type III) - uncommon
  • Ghast - uncommon
  • Ghoul - rare
  • Goristroi - very rare
  • Hezrou (Type II) - common
  • Manes - common
  • Mephit - common
  • Nabassu - rare
  • Nightmare - very rare
  • Quasit - common
  • Rutterkin - common
  • Succubus - rare
  • Thunder Beast - common
  • Type IV - rare
  • Type V - rare
  • Type VI - very rare
  • Vrock (Type I) - common

Probabilities of encounter are not stated as a percentage, for there will usually be other sorts of creatures on a given plane of the Abyss. For example, on Demogorgon's several layers there will be many sorts of vicious apes, reptiles (including dinosaurs), and bird-like monsters. Similarly, on Jiblex's plane there will be slimes, deadly puddings, jellies, and various amoeboid monsters. Orcus' manifold layers are populated with skeletal monsters, various sorts of zombies, huecuvae, shadows, sheet phantoms, vampires, and death knights. Yeenoghu's vast plane of the Abyss abounds with hyenas and |hyaenodons, gnolls, ghasts, ghouls, and possibly a few trolls. Other planes are populated by insects, arachnids, worms and slugs, fungi and fungoid monsters, and so on.

Some layers of the Abyss are devoid of most of the typical inhabitants of other levels. The liquid plane ruled by Dagon, for instance, does have hezrou (type II) and a form of dretch, but the other inhabitants are octopi, squids, kraken, sea snakes, eels, weird fish, and horrible fish-monsters. In short, use your imagination and creativity to develop these areas.