Here is a mind flayer for pf2e – PWoL version. Add 12 to AC, Skills, Saves, To-Hit, and all DCs to have a standard version. My PF2E players are delving the Underdark in search of Erin Cinlu and got the “M2” random encounter from the original D module.
Mind Flayer [Creature 12]
LE Medium Aberration, Psionic
Perception +10; darkvision
Languages Aklo, Common, Undercommon, Telepathy 120 ft.
Skills Arcana +9, Deception +11, Intimidation +11, Occultism +11, Stealth +8
Str +3, Dex +4, Con +4, Int +6, Wis +5, Cha +6
Items black robes, jewelled focus rod
AC 20; Fort +8, Ref +9, Will +12
HP 215; Resistances mental 10
Immunities controlled
Speed 30 ft.
Melee [◆] Tentacle +12 (reach 10 ft., magical), Damage 2d10+9 (20) bludgeoning plus Grab and Extract Brain
Melee [◆] Debilitating Claw +12 (agile, curse, occult), Damage 2d8+9 (18) slashing and the target must succeed at a DC 20 Fortitude save or become clumsy 1. Each time a target fails an additional save against this ability, the condition value increases by 1 (to a maximum of clumsy 4). This condition value decreases by 1 every 24 hours.
Occult Innate Spells (Psionic) DC 20, attack +12; 4th outcast’s curse, phantom pain, suggestion; 3rd hypnotic pattern, levitate, locate, mind reading; 2nd mirror image; Cantrips (4th) chill touch, detect magic, mage hand, message, read aura; Constant (4th) tongues
Mind Blast [◆◆] (Occult, Mental, Evocation) 30-foot cone, DC 20 Will save. Cooldown: 1d4 rounds.
- Failure: 12d6 mental damage (avg 42) and Stunned 1d4 actions.
- Success: Half damage.
- Critical Failure: 12d6 mental damage and Stunned 2d4 actions.
Extract Brain [◆] (Mental, Death) Requirements: The Mind Flayer has a creature Grabbed in its tentacles. The target must succeed at a DC 20 Fortitude save.
- Failure: 8d10+9 piercing damage (avg 53). If reduced to 0 HP, it dies instantly.
- Success: Half damage.
- Critical Failure: Death, regardless of hit points.
Psionic Domination [◆] (Occult, Mental, Psionic) The Mind Flayer casts dominate on a creature within telepathy range. This counts against its daily spell slots (4th level).
Tactics
Before Combat: Uses mirror image and invisibility to set ambushes.
During Combat: Opens with Mind Blast to disable, then grapples with tentacles. Prioritizes spellcasters and weaker minds with dominate.
Morale: Escapes via dimension door or plane shift if near defeat.