Ghaggurath

Gargantuan aberration, neutral evil

Armor Class 12
Hit Points 252 (24d10 + 120)
Speed 20 ft., climb 20 ft.

STR	DEX	CON	INT	WIS	CHA
19 (+4)	14 (+2)	20 (+5)	16 (+3)	30 (+10)	25 (+7)

Saving Throws Con +11, Wis +16, Cha +13
Skills Arcana +9, Insight +16, Nature +9, Perception +16, Persuasion +13
Damage Resistances acid, cold, fire, thunder; bludgeoning, piercing and slashing damage from non-magical attacks
Condition Immunities charmed, grappled, prone
Senses darkvision 120 ft., passive Perception 26
Languages Abyssal, Common, Giant, Goblin, Infernal, Terran, Undercommon; telepathy 100 ft.
Challenge 18 (20,000 XP)

SPECIAL TRAITS

• Aberrant Ground. The ghaggurath in a 10-foot radius around the mouther is doughlike difficult terrain. Each creature that starts its turn in that area must succeed on a DC 19 Strength saving throw or have its speed reduced to 0 until the start of its next turn.
• Create Thrall. A victim whose Wisdom score is reduced to 0 from the ghaggurath’s poison is automatically dominated (as a dominate monster spell). This effect lasts until the thrall worm is removed and at least 1 point of Wisdom is restored. The ghaggurath does not have to concentrate each day to maintain this effect, and a dominated creature does not receive a save to break the effect. If the ghaggurath is slain, any thrall under its command falls unconscious and remains so until the thrall worm is removed and at least 1 point of Wisdom is restored.
• Legendary Resistance (3/Day). If the ghaggurath fails a saving throw, it can choose to succeed instead.
• Magic Resistance. The ghaggurath has advantage on saving throws against spells and other magical effects.
• Magic Weapons. Ghaggurath’s weapon attacks are magical.
• Thrall Worm Poison. The target exposed to this poison must make a DC 19 Constitution saving throw or become poisoned for 1 hour. While poisoned the target loses 1d6 Wisdom points per round. The target may repeat the saving throw at the end of its turn. It takes two consecutive successful saving throws to end the poison effect.

ACTIONS

• Multiattack. The ghaggurath makes eight bite attacks – but no two attacks against the same target. It may replace up to 4 bite attacks with a Spit Thrall Worm attack instead.
• Bite. Melee Spell Attack: +16 to hit, reach 20 ft., one creature. Hit: 23 (3d8 + 10) piercing damage. If the target is Huge or smaller, it must succeed on a DC 18 Strength saving throw or be forced prone. If the target is killed by this damage, it is absorbed into the ghaggurath. The target is also exposed to Thrall Worm Poison.
• Spit Thrall Worm. The ghaggurath ejects a fleshy worm approximately 1 foot long, called a thrall worm, at a single target to a range of 50 feet. The worm hits and bites the target if it fails a DC 16 Dexterity saving throw. When a thrall worm strikes a target, it quickly burrows into the target’s body. This worm can safely be removed with a successful DC 25 Wisdom (Medicine) or by the application of any healing or restoration spell; otherwise removing the worm deals an extra 1d6 points of damage to the target. After 1d4 rounds, the worm works its way so deep into the target’s body that it can only be removed by cutting open the area (dealing 1d8 points of damage to the victim) before attempting a Wisdom (Medicine) or casting a healing spell. Once a worm is removed from its host, it dies. Any effect that removes disease destroys the worm. As long as a thrall worm remains inside a target, the target cannot heal the Wisdom damage dealt by the ghaggurath’s poison. A creature can only ever have one thrall worm inside it at one time; it can however be attacked and bitten by multiple thrall worms.