Illithilich

Medium Undead, any evil alignment

Armor Class 19 (natural armor)

19 (natural armor) Hit Points 150 (20d8 + 60)

150 (20d8 + 60) Speed 30ft.

STR DEX CON INT WIS CHA 11 (+0) 18 (+4) 16 (+3) 22 (+6) 16 (+3) 17 (+3)

Saving Throws Con +10, Int +13, Wis +10, Cha +10

Con +10, Int +13, Wis +10, Cha +10 Skills Arcana +20, History +13, Insight +10, -- Perception +10

Arcana +20, History +13, Insight +10, -- Perception +10 Damage Resistances cold, lightning, necrotic, psychic

cold, lightning, necrotic, psychic Damage Immunities poison; bludgeoning, piercing, and slashing from nonmagical attacks

poison; bludgeoning, piercing, and slashing from nonmagical attacks Condition Immunities charmed, exhaustion, frightened, paralyzed, poisoned

charmed, exhaustion, frightened, paralyzed, poisoned Senses truesight 120 ft., passive perception 20

truesight 120 ft., passive perception 20 Languages Common, Deep Speech, Undercommon, plus up to two others, telepathy 120 ft.

Common, Deep Speech, Undercommon, plus up to two others, telepathy 120 ft. Challenge 23 (50,000 XP)

Innate Spellcasting (Psionics). The illithilich's innate spellcasting ability is Intelligence (spell save DC 21). It can innately cast the following spells, requiring no components:

At will:detect thoughts, levitate

3/day each: dominate monster, plane shift(self only)

Legendary Resistance (3/Day). When the illithilich fails a saving throw, it can choose to succeed instead.

Magic Resistance. The illithilich has advantage on saving throws against spells and other magical effects.

Rejuvenation. If it has a phylactery, a destroyed illithilich gains a new body in 1d10 days, regaining all its hit points and becoming active again. The new body appears within 5 feet of the phylactery.

Spellcasting. The illithilich is a 20th-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 21, +13 to hit with spell attacks). The illithilich has the following wizard spells prepared:

Cantrips (at will): mage hand, prestidigitation, ray of frost

1st-level (4 slots): charm person, detect magic, magic missile, shield, thunderwave

2nd-level (3 slots): crown of madness, hold person, ray of enfeeblement

3rd-level (3 slots): animate dead, counterspell, fly, lightning bolt

4th-level (3 slots): blight, evard's black tentacles, greater invisibility

5th-level (3 slots): cloudkill, hold monster, scrying

6th-level (2 slots): disintegrate, otiluke's freezing sphere

7th-level (2 slots): finger of death, prismatic spray

8th-level (1 slot): feeblemind, power word stun

9th-level (1 slot): foresight, power word kill

Actions

Paralyzing Tentacles. Melee Weapon Attack: +13 to hit, reach 5ft., one creature. Hit 28 (4d10 + 6) psychic damage plus 10 (3d6) cold damage. The target must succeed on a DC 18 Constitution saving throw or be paralyzed for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. On a hit: If the target is medium or smaller, it is grappled (escape DC 18).

Extract Brain and Soul. Melee Weapon Attack: +13 to hit, reach 5ft., one incapacitated humanoid grappled by the illithilich. Hit 55 (10d10) piercing damage plus 35 (10d6) necrotic damage. If this damage reduces the target to 0 hit points, the illithilich kills the target by extracting and eating its brain, as well as sending the soul of the creature to its phylactery (if it has one).

Mind Blast (Recharge 5-6). The illithilich magically emits psychic energy in a 60-foot cone. All creatures in that area must succeed at a DC 21 Intelligence saving throw or take 33 (6d8 + 6) psychic damage and be stunned for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Legendary Actions

The illithilich can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The illithilich regains spent legendary actions at the start of its turn.

Cantrip. The illithilich casts a cantrip

Attack. The illithilich makes one attack.

Cast a Spell (Costs 2 Actions). The illithilich casts a spell of 1st-level or higher.

Frightening Thoughts (Costs 2 Actions). The illithilich releases a stream of nightmarish thoughts in a 20-foot radius around it, all creatures in the area must succeed on a DC 18 Wisdom saving throw against this effect or become frightened for 1 minute. The target can repeat the save at the end of each of its turns, ending the effect on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to this ability for the next 24 hours.

Disrupt Life(Costs 3 Actions). Each non-undead creature within 20 feet of the illithilich must make a DC 18 Constitution saving throw, taking 28 (8d6) necrotic damage on a failed save, or half as much damage on a successful one.