Illithid

Scattered survivors of a world-ruining, multiversal empire, mind flayers lurk in secret conclaves hidden deep within Material Plane worlds. Within their alien sanctuaries, these wicked masterminds—also known as illithids—reshape the Underdark and its inhabitants to serve their unfathomable whims. Mind flayers are feared for their psionic powers, which allow them to stun and control other creatures, and for their horrific method of feeding: using their four slimy tentacles to extract the brains of their victims.

Mind flayers are infamous plotters and manipulators, concocting plans that reach beyond their subterranean realms. Aside from using their psionic powers to control others, mind flayers often experiment with their own bizarre life cycles, implanting other creatures with illithid young to create unnatural servants. Creatures such as grimlocks and intellect devourers result from mind flayers’ biological tampering, while other Underdark-dwelling monsters—including kuo-toa, quaggoths, and troglodytes—often serve illithid masters. Githyanki and githzerai have a long adversarial history with mind flayers and bear the scars of illithid manipulation.