Gargantuan giant, chaotic evil
Armor Class 15 (natural armor)
Hit Points 512 (31d20 + 186)
29 (+9) 16 (+3) 22 (+6) 11 (+0) 18 (+4) 3 (-4)
Saving Throws Con +14, Wis +12, Cha +4
Damage Resistances bludgeoning, piercing, and slashing from nonmagical attacks, poison.
Condition Immunities frightened, poisoned, charmed
Senses darkvision 120 ft., passive Perception 21
Languages Giant, Undercommon
Keen Senses. The troll has advantage on Wisdom (Perception) checks that rely on smell or sight.
Regeneration. The troll regains 15 hit points at the start of its turn. If the troll takes acid or fire damage, it regains only 10 hit points at the start of its next turn. The troll dies only if it is hit by an attack that deals 30 or more acid or fire damage while the troll has 0 hit points.
Legendary Resistance.(3/day) If the troll fails a saving throw, it can choose to succeed instead.
Magic Resistance. The troll has advantage on saving throws against spells and other magical effects.
Loathsome Limbs. Whenever the troll takes at least 15 slashing damage at one time, roll a d20 to determine what else happens to it:
1-10: Nothing else happens.
11-14: One leg is severed from the troll.
15-18: One arm is severed from the troll.
19-20: The troll is decapitated, but the troll dies only if it can't regenerate. If it dies, so does the severed head.
If the troll finishes a short or long rest without reattaching a severed limb or head, the part regrows. At that point, the severed part dies. Until then, a severed part acts on the troll's initiative and has its own action and movement.
A severed part has AC 13, 10 hit points, and the troll's Regeneration trait.
A severed leg is unable to attack and has a speed of 5 feet.
A severed arm has a speed of 5 feet and can make one claw attack on its turn, with disadvantage on the attack roll unless the troll or one of its heads can see the arm and its target.
The severed head has a speed of O feet and the troll's Keen Smell trait. It can make a bite attack (Bite. Melee Weapon Attack: +17 to hit, reach 10 ft., one target. Hit: 13 (1d8 + 9) piercing damage plus 5 (1d10) poison damage.) but only against a target in its space.
Multiattack. The troll makes five attacks: three with Rend and two with its claws.
Rend. Melee Weapon Attack. +17 to hit, reach 15 ft. one target. Hit: 31 (4d10+9) slashing damage plus 5 (1d10) poison damage.
Claws. Melee Weapon Attack: +17 to hit, reach 10 ft. one target. Hit: 20 (3d6+9) slashing damage.
Whirlwind of Claws (Recharge 5-6). Each creature within 10 feet of the troll must make a DC 19 Dexterity saving throw, taking 44 (8d10) slashing damage on a failed save, or half as much damage on a successful one.
Fling Limb.(3/day) Ranged Weapon Attack. +14 to hit range 60/240 ft., one target. Hit: 13 (1d10+8) bludgeoning damage. If the limb hits a Medium or smaller creature, that creature has the grappled condition (escape DC 17). The limb has the statistics of a dire troll amalgam, except for the following:
It is Large, it has 100 hit points, its speed is 40 ft., it doesn't have a challenge rating or legendary resistance, and the only action it can make is the Attack action, which it can only use to grapple.
Until this grapple ends, the target has the restrained condition and takes 31 (4d10+9) slashing damage at the start of each of its turns. If the limb is not destroyed within 24 hours of being flung, roll a d12; On a roll of 12, the limb regenerates into a dire troll. Otherwise, the limb withers away.