Source: Alien Archive 2, pg(s). 82
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Mi-go communicate by clicking their pincers and changing the colour of their heads; this sign language can be learnt but usually not 'spoken' by other creatures. A mi-go can speak in a strange, buzzing voice, but only when forced to. Mi-go do not need to breathe and can fly through outer space at an incredible speed. Their claws are capable of swiftly and painfully performing surgical operations upon hapless victims.
Mi-go view the universe as a canvas to be controlled and mastered. They consider themselves superior beings and can remake the flesh of victims to be ideal servitors or just to fit their aesthetics, all while keeping them alive (and insane) despite invasive surgeries, like the extraction of the subject's brain into a mi-go brain cylinder. Using their technology and malleable bodies, mi-go create mi-go hollowskins resembling their victims to infiltrate societies.
Mi-go meld magic and faith with science and technology, considering both largely the same. Most of them worship the entities of the Elder Mythos, and consider themselves something akin to students of their gods.