I'm going to build a couple versions of him and see which I like most.
First up is the doppelganger warlock with the
intellect devourer symbioses. Man, I get excited just thinking about that delicious combination. I'm thinking doppelganger warlock 14 so he can make thralls.
Mechanically, wow, what a combo! Doppelgangers can read surface thoughts. Intellect devourer gives them blindsight 60ft and can detect sentience 300ft. Warlocks making the pact with the Great Old One can communicate telepathically with anyone within 30ft. That all adds up very nicely.
On to the nitty gritty warlock bitty's:
Greel the Mind Raker
Medium monstrosity (shapechanger), chaotic evil
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Armor Class
Hit Points (22d8 +)
Speed 30 ft.
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STR DEX CON INT WIS CHA
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Saving Throws Wis +5, Cha +10
Skills Deception +6, Insight +3, Arcana, Intimidation
Condition Immunities charmed
Senses darkvision 60 ft., passive Perception 11
Languages Common
Challenge 11
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Special Equipment. Greel has an
umbral of hadar.
Spellcasting. Greel is a 14th-level spellcaster who uses charisma as his spellcasting ability (spell save DC. + to hit with spell attacks.) Rath has the following spells prepared from the warlock and wizard spell list*:
Cantrips (at will): chill touch, eldritch blast, mage hand, prestidigitation
5th level (3 slots): arms of hadar, unseen servant, armor of agathys, dissonant whispers*, tasha's hideous laughter*, darkness, suggestion, detect thoughts*, phantasmal force*, fly, hunger of hadar, clairvoyance*, sending*, dimension door, banishment, dominate beast*, evard's black tentacles*, dream, scrying, contact other plane, dominate person*, telekenesis*
Otherworldly Patron: The Great Old One
Pact Boon: Pact of the Chain (Intellect Devourer familiar), though Pact of the Tome could be a sweet option as well
6 Invocations Known - Devil's Sight, Voice of the Chain Master, Beguiling Influence, One With Shadows, ??, ??
12 Spells Known (5th lvl)
Cantrips - Chill Touch, Eldritch Blast, Mage Hand, Prestidigation
1st - Arms of Hadar, Unseen Servant, Armor of Agathys, Dissonant Whispers*, Tasha's Hideous Laughter*
2nd - Darkness, Suggestion, Detect Thoughts*, Phantasmal Force*
3rd - Fly, Hunger of Hadar, Clairvoyance*, Sending*
4th - Dimension Door, Banishment, Dominate Beast*, Evard's Black Tentacles*
5th - Dream, Scrying, Contact Other Plane, Dominate Person*, Telekenesis*
Not familiar with the warlock list at all, feel free to suggest better spell choices. * spells are ones given by The Great Old One, praise be His Unknowable Name.
With these spells, Greel can keep tabs on pretty much anyone. He knows the location of anyone nearby, he can read their thoughts, he can speak into their minds, enter their dreams, spy on them with Scrying.. a bunch. Can even ask The Great Old One some questions.
Feats: ???