Spell save DC 16

3/day each: Fear, Hunger of Hadar, Blight

Sight: Blind

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

Abyssal Regeneration. The Abyssal Titan regains 10 hit points at the start of its turn if it has at least 1 hit point.

Multiattack. The Abyssal Titan makes two attacks with its Hammer or Tentacles.

Hammer. Melee Weapon Attack: +8 to hit, reach 15 ft., one target.
Hit: 29 (3d12 + 8) bludgeoning damage plus 13 (3d8) necrotic damage.

Tentacles. Melee Weapon Attack: +10 to hit, reach 20 ft., one target.
Hit: 22 (4d6 + 8) bludgeoning damage plus 7 (2d6) psychic damage. The target is grappled (escape DC 18). Until this grapple ends, the target is restrained.

When restrained, as part of its turn, the Abyssal Titan can use Slam:
Slam Hit: 22 (6d6) bludgeoning damage.

Abyssal Quake (Recharge 5-6).
The Abyssal Titan slams its hammer into the ground, releasing dark energy. Each creature within a 30-foot radius of the hammer must make a DC 16 Dexterity saving throw.

• On a failed save: A creature takes 13 (3d8) bludgeoning damage and 9 (2d8) necrotic damage and is knocked prone.
• On a successful save: A creature takes half as much damage and isn't knocked prone.

The area becomes difficult terrain as writhing black tendrils sprout from the ground. Any creature except the Abyssal Titan that starts its turn in the area takes 7 (2d6) necrotic damage.

Any creature except the Abyssal Titan that ends its turn in the area must succeed on a Dexterity saving throw or take 7 (2d6) necrotic damage from the black tendrils.

The area lasts until the hammer is picked up.

Aggressive. As a bonus action, the Abyssal Titan can move up to its speed toward a hostile creature that it can hear.