Mind flayers speak Undercommon but prefer to communicate telepathically.

Combat

Mind flayers like to fight from a distance, using their psionic abilities, particularly their mind blast. If pressed into melee combat, a mind flayer lashes its enemies with the tentacles ringing its mouth.

Mind Blast (Sp): This attack is a cone 60 feet long. Anyone caught in this cone must succeed at a Will save (DC 17) or be stunned for 3d4 rounds. Mind flayers often hunt using this power and then drag off one or two of their stunned victims to feed upon.

Psionics (Sp): At will-astral projection, charm monster, detect thoughts, levitate, plane shift, and suggestion. These abilities are as the spells cast by an 8th-level sorcerer (save DC 13 + spell level).

Improved Grab (Ex): To use this ability, the mind flayer must hit a Small to Large creature with its tentacle attack. If it gets a hold, it attaches the tentacle to the opponent's head. A mind flayer can grab a Huge or larger creature, but only if it can somehow reach the foe's head. After a successful grab, the mind flayer can try to attach its remaining tentacles with a single grapple check. The opponent can escape with a single successful grapple check or Escape Artist check, but the mind flayer gets a +2 circumstance bonus for every tentacle that was attached at the beginning of the opponent's turn.

Extract (Ex): A mind flayer that begins its turn with all four tentacles attached and successfully maintains its hold automatically extracts the opponent's brain, instantly killing that creature.

Telepathy (Su): Mind flayers can communicate telepathically with any creature within 100 feet that has a language.