Armor Class 16
Hit Points 143 (26d8 + 26)
Speed 30 ft., fly 30 ft.
Saving Throws DEX +6, INT +9, WIS +7, CHA +7
Skills Arcana +13, Insight +7, Perception +7, Stealth +6
Damage Immunities psychic
Condition Immunities charmed, frightened
Senses Darkvision 120 ft., passive Perception 17
Languages Deep Speech, Undercommon; telepathy 120 ft.
Challenge 11
Magic Resistance. The mind flayer has Advantage on saving throws against spells and other magical effects.
Multiattack. The mind flayer makes three Arcane Tentacles attacks.
Arcane Tentacles. m,r +9, reach 5 ft. or range 120 ft. Hit: 27 (4d10 + 5) Psychic damage, and the mind flayer can teleport the target up to 30 feet to an unoccupied space the mind flayer can see on a surface or liquid large enough to support the target. If this damage reduces the target to 0 Hit Points, the mind flayer kills it and magically devours its brain.
Mind Burst (Recharge 5–6). int DC 17, each creature in a 40-foot Emanation originating from the mind flayer. 41 (8d8 + 5) Psychic damage, and the target has the Stunned condition until the end of the mind flayer's next turn. Half damage only.
Monster Manual (2024), p. 214