Shan

The Shan, commonly referred to as The Insects from Shaggai, are a species of alien which appear in the H.P. Lovecraft-inspired Cthulhu Mythos.

Description
Small, multi-limbed insectoid creatures who possess a high degree of intelligence and scientific competence, the Shan are a semi-parasitic race of interstellar refugees. They posses a six-lobed brain which allows them to follow three entirely different trains of thought simultaneously, a factor which likely contributes to their technological savvy.

Shan are also capable of working their way into the cranium of certain races - a process known as Kirlian Phasing - subsequently using their considerable telepathic abilities to slowly turn the host body into little more than a puppet with which to further their inscrutable goals.

When on Earth, however, the Shan typically avoid direct sunlight, as the electromagnetic rays emitted by the sun are highly toxic to their alien physiology.

History
Originating on the planet Shaggai, the Shan were forced to flee their home world when the Outer God known as Ghroth passed nearby, causing the planet to self-destruct. Fortunately for the Azathoth-worshiping Shan, they had constructed strange pyramid-temples to their god, which doubled as trans-dimensional gateways, and thus a portion of their race were able to escape the annihilation of their home.

Finally making their way to Earth after attempting to settle various other unsuitable worlds, the survivors established a colony in the Severn Valley of England, where they remain to this day, taking possession of any who wander too close to their concealed pyramid-temple.

Trivia

 * The Insects of Shaggai are a frequent opponent in pen-and-paper RPG Delta Green.