Large demon, chaotic evil

Armor Class: 17

Hit Points: 150 (12d10 + 72) 12d10+72

Speed: 40 ft

STR

22 +6

DEX

12 +1

CON

22 +6

INT

14 +2

WIS

14 +2

CHA

18 +4

Saving Throws: Str +9, Con +9, Cha +7

Damage Resistances: cold, fire, lightning; bludgeoning, piercing, and slashing from nonmagical attacks

Condition Immunities: charmed, frightened, poisoned

Senses: darkvision 120 ft., passive Perception 12

Languages: Abyssal, telepathy 120 ft.

Challenge Rating: 10

Proficiency Bonus: 4

Actions

Multiattack. The Tyrant makes two Crushing Fist attacks.
  Crushing Fist. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 21 (3d10 + 5) bludgeoning damage plus 9 (2d8) fire damage.
  Fel Roar (Recharge 5–6). The Tyrant releases a guttural roar. Each creature of the Tyrant’s choice within 30 feet must succeed on a DC 17 Constitution saving throw or be stunned until the end of their next turn.

The Demonic Tyrant’s lair is a throne of jagged obsidian and blazing pits. While in its lair, the following effects apply:

• Demons summoned within the lair gain temporary hit points equal to their CR × 5.
• At initiative count 20 (losing ties), the lair causes a tremor. All non-demons on the ground must succeed on a DC 15 Dexterity saving throw or be knocked prone.
• Shadowflame periodically erupts from runes along the walls, dealing 3d8 fire and 3d8 shadow damage to one random creature not allied with the Tyrant each round (Dex save DC 16 for half).