Armored Troll (5e Creature)
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Large giant, chaotic evil
Death Burst. When the troll dies, it explodes in a storm of metal fragments. Each creature within 10 feet of it must make a DC 16 Dexterity saving throw, taking 21 (6d6) slashing damage on a failed save, or half as much damage on a successful one.
Drive the Nails. A creature that isn't hostile to the troll within 5 feet of the troll can use an action on its turn to strike an exposed piece of metal on the troll's body. The troll takes 7 (2d6) piercing damage and gains advantage on all melee weapon attack rolls it makes before the end of its next turn.
Regeneration The troll regains 10 hit points at the start of its turn. If the troll takes acid or fire damage, this trait doesn't function at the start of the troll's next turn. The troll dies only if it starts its turn with 0 hit points and doesn't regenerate.
Multiattack. The troll makes three attacks: one with its bite and two with its claws.
Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 9 (1d10 + 4) piercing damage.
Claw. Melee Weapon Attack: +7 to hit, reach 5 ft., one target.Hit: 13 (2d8 + 4) slashing damage.
Trolls are resilient and powerful monsters, feared for their sheer strength and regenerative properties. Yet, for some, this is not enough. Using cruel surgeries, weapons and pieces of metal of varying sizes are forcibly implanted into a still-living troll, turning its claws into rending blades and imbuing its already thick skin with the toughness of steel. However, the troll lives in constant agony, only kept alive by its regeneration, its incredible pain driving it into a berserker rage. In time, the troll's body will force the metal out, so any who wish to make use of armored trolls for an extended period of time must repeat the process numerous times.