Elder Brain

Large aberration, lawful evil
Armor Class 10
Hit Points 210 (20d10 + 100)
Speed 5 ft., swim 10 ft.
STR
15 (+2)
DEX
10 (+0)
CON
20 (+5)
INT
21 (+5)
WIS
19 (+4)
CHA
24 (+7)
Saving Throws Int +10, Wis +9, Cha +12
Skills Arcana +10, Deception +12, Insight +14, Intimidation +12, Persuasion +12
Senses blindsight 120 ft., passive Perception 14
Languages understands Common, Deep Speech, and Undercommon but can't speak, telepathy 5 miles
Challenge 14 (11500 XP)
Creature Sense.
Innate Spellcasting (Psionics).
Legendary Resistance (3/Day).
Magic Resistance.
Telepathic Hub.
ACTIONS
Tentacle.
Mind Blast (Recharge 5–6).
Psychic Link.
Sense Thoughts.
LEGENDARY ACTIONS
Tentacle.
Break Concentration.
Psychic Pulse.
Sever Psychic Link.

This full creature's stat block is not available (not OGL).

Volo´s Guide to Monsters
Elder Brain