Swordwing Cogivore - Medium Humanoid (CR 11)

"Whilst the armoured fighters of their kind held us at bay, slashing and ripping into us with savage and precise effect, the slightly smaller ones darted here are there, dodging out of the way of our archer's fire, and unleashing unseen bursts of crushing psychic power. What had started as an ambush, quickly dissolved in abject chaos, and then a rout, and I am not ashamed to admit that I was part of that mindless, panicked retreat."

- From battle report of Undurgoin Khozzakar, Daelndorin Warlord. 

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Best I could find...(from http://nathanrosario.deviantart.com/art/Mi-Go-Concept-5-187231557)
The Swordwings come in a number of varieties, apparently evolved to fulfill different roles in either day to day life, or in defense of their hives. The cogivore is somewhat smaller than their warrior kin, and over all is substantially less of a threat. However, they wield potent psionic abilities, and can easily destroy an enemy physically and psychically, although their role tends to be to hang back and to snipe at enemies whilst their more physically potent brethren tear into them. 

The Illithids of Arbel'Verdnaniss have tried several times to control these things, in order to use them as watchdogs or even the hosts for their foul larvae.However, these have always ended in disaster, as the beasts are immune to any kind of magical or psionic control, and their distress was somehow sensed by the rest of the hive, who sent soldiers to rescue their lost brethren.