Seven Kingdoms: Seowyn's Crossing
Illithids, or mind flayers as they are known to most folk on Tol, are evil entities from the Far Realm. The first mind flayers must’ve appeared on Tol long ago, as pictures of them warring with the so-called Old Ones of central Aldorath have been discovered in some Old One excavations.
They are powerful in the ways of psionics, being capable of stunning a foe with the power of their minds. They are known to take slaves, as well as to prefer to dine on the brains of sentient creatures.
Like most Far Realms threats, they consider themselves to be the most powerful force that exists and have nothing but contempt for “lesser races”.