Roughly the same size as an adult human, the Mi-go appear crustacean or insectiod in nature but are actually a type of fungal lifeform. Their heads are lozenge-shaped, with a mane of small antennae, their bodies have multiple pairs of limbs attached to the thorax, and they sport a pair of large wings which, while not particularly effective in an atmosphere, allow them to traverse the depths of space at a considerable speed. In addition, sufficiently low temperatures will simply cause a Mi-go to enter a kind of suspended animation; subsequent exposure to a suitable heat source will reanimate the creature, whereby it will continue about its business with no ill effects.
Some sources also state that the Mi-go cannot be captured through the use of conventional recording devices, as their bodies are composed of a strange otherworldly substance which does not show up on such equipment.
HistoryWhere the Mi-go originate is a mystery, but it is known that they have established a colony on Yuggoth, a planet on the outskirts of our solar system, and that at least a handful make their home on Earth, although they are inimically hostile to the human race. They have been known to transport samples of our species to Yuggoth by removing the brain and inserting it into a cylindrical contraption. This device is fitted with sensory equipment which allows the prisoner to see and hear as normal, but does not permit any interaction with its surroundings. The reason the Mi-go indulge in this practice is unknown.
The Mi-go are also believed to worship (or at least pay lip-service to) the Outer Gods Shub-Niggurath and Nyarlathotep, and their colony on Yuggoth is known to house many designs which can be used in the furtherance of the rituals described in the Necronomicon; however, the Mi-Go have a mystical sense which allows them to tell when these designs are being transcribed by humans, and they will ruthlessly hunt down and exterminate any with copies in their possession.