Thornheart Guardian

Large construct, lawful evil

Armor Class 18 (natural armor)
Hit Points 133 (14d10 + 56)
Speed 30 ft.

19 (+4) 10 (+0) 18 (+4) 7 (-2) 14 (+2) 1 (-5)

Skills Perception +6
Damage Resistances bludgeoning, piercing, and slashing from nonmagical attacks
Damage Immunities poison, psychic
Condition Immunities charmed, exhaustion, frightened, paralyzed, petrified, poisoned
Senses darkvision 60 ft., passive Perception 16
Languages understands the languages of its creator but can’t speak
Challenge 9 (5,000 XP)


  • Immutable Form. The thornheart guardian is immune to any spell or effect that would alter its form
  • Magic Resistance. The thornheart guardian has advantage on saving throws against spells and other magical effects.
  • Magic Weapons. The thornheart guardian’s weapon attacks are magical.
  • Woodland Walk. Difficult terrain composed of nonmagical plants doesn’t cost the thornheart guardian extra movement. In addition, the thornheart guardian can pass through nonmagical plants without being slowed by them and without taking damage from them if they have thorns, spines, or a similar hazard.


  • Multiattack. The thornheart guardian makes three attacks: two with its barbed greatsword and one with its thorny whip.
  • Barbed Greatsword. Melee Weapon Attack +8 to hit, reach 5 ft, one target. Hit: 13 (2d8 + 4) slashing damage plus 7 (2d6) piercing damage.
  • Thorny Whip. Melee Weapon Attack: +8 to hit, reach 15 ft., one target. Hit: 11 (2d6 + 4) piercing damage, and the target is grappled (escape DC 16) if it is a Medium or smaller creature. Until this grapple ends, the target is restrained, the guardian can automatically hit the target with its thorny whip, and the guardian can’t make thorny whip attacks against other targets.
  • Grasp of the Briar (Recharge 5-6). The thornheart guardian summons grasping, thorny vines to impede and drain the life of its foes. The ground within 20 feet of the thornheart guardian becomes difficult terrain for 1 minute. This difficult terrain doesn’t cost the thornheart guardian extra movement. A creature that enters or starts its turn in the area must succeed on a DC 16 Strength saving throw or be restrained by the plants. A restrained creature takes 7 (2d6) necrotic damage at the start of each of its turns. A creature, including the restrained target, can take its action to break the target free of the vines by succeeding on a DC 16 Strength check.


A hulking figure clad in a black armor adorned with thorny ornaments slowly walks forward, seemingly unhindered by the thick vegetation of the surrounding woods.

Thornheart guardians are unyielding and merciless defenders of the forest domains of hags and other sinister fey. They are the twisted cousins of green knights of the woods, and good-aligned fey often send green knights on hunts to destroy thornheart guardians and their creators.

Shadow Origins. Thornheart guardians are created from the bodies and souls of unfortunate knights who foolishly fell for the charms of hags or dark fey and swore eternal servitude to them. In unholy ceremonies, hags fuse the knights’ bodies with armor forged in the Shadow Realm then transform the knights’ hearts into a cluster of enchanted thorns.

Relentless and Loyal. The thornheart guardian is a terror to behold. Once it has found its mark, it doesn’t back down until the enemies of its sinister liege have been slain. Its enchanted heart gives it power over the plants around it, and it uses these plants to capture and kill its enemies.

Construct Nature. The thornheart guardian doesn’t require air, food, drink, or sleep.

Section 15: Copyright Notice

Tome of Beasts 2. © 2020 Open Design LLC; Authors Wolfgang Baur, Celeste Conowitch, Darrin Drader, James Introcaso, Philip Larwood, Jeff Lee, Kelly Pawlik, Brian Suskind, Mike Welham.

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