Yagnoloth

Large fiend (yugoloth), neutral evil
Armor Class 17 (natural armor)
Hit Points 147 (14d10 + 70)
Speed 40 ft.
STR
19 (+4)
DEX
14 (+2)
CON
21 (+5)
INT
16 (+3)
WIS
15 (+2)
CHA
18 (+4)
Saving Throws Dex +6, Int +7, Wis +6, Cha +8
Skills Deception +8, Insight +6, Perception +6, Persuasion +8
Damage Resistances cold, fire, lightning; bludgeoning, piercing, and slashing from nonmagical attacks
Damage Immunities acid, poison
Condition Immunities poisoned
Senses blindsight 60 ft., darkvision 60 ft., passive Perception 16
Languages Abyssal, Infernal, telepathy 60 ft.
Challenge 11 (7200 XP)
Innate Spellcasting.
Magic Resistance.
Magic Weapons.
ACTIONS
Multiattack.
Electrified Touch.
Massive Arm.
Life Leech.
Battlefield Cunning (Recharge 4–6).
Teleport.

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

Mordenkainen´s Tome of Foes
Yagnoloth