Medium monstrosity, unaligned

Armor Class 15 (natural armor)
Hit Points 127 (15d8 + 60)
Speed 30 ft., swim 30 ft., climb 20 ft .

16 (+3) 10 (+0) 19 (+4) 3 (–4) 12 (+1) 3 (–4)

Skills Stealth +6
Damage Resistances slashing, piercing
Damage Immunities fire, poison
Condition Immunities poisoned
Senses blindsight 10 ft., darkvision 60 ft., passive Perception 11
Challenge 5 (1,800 XP)
Proficiency Bonus +3


  • Lava Bound. The vorthropod can exist outside of lava or magma for up to 4 hours each day. If it starts its turn outside of lava and didn’t take fire damage since the end of its previous turn, its shell begins to cool and harden. While its shell is hardened, it has a walking speed of 20 feet, an Armor Class of 18, and vulnerability to bludgeoning damage. If it starts its turn in lava or if it took fire damage since the end of its previous turn, its shell becomes molten again. If the vorthropod remains outside of lava for more than 4 hours, its shell becomes petrified, transforming into basalt, and the vorthropod within goes into hibernation. Its body returns to normal if it is submerged in lava or magma for 1 round. It can stay petrified in hibernation for up to 1d% + 10 years, after which it dies.
  • Lava Camouflage. The vorthropod has advantage on Dexterity (Stealth) checks made to hide in lava and volcanic terrain.
  • Molten Shell. If the vorthropod’s shell isn’t hardened, a creature that touches the vorthropod or hits it with a melee attack while within 5 feet of it takes 7 (2d6) fire damage.


  • Multiattack. The vorthropod makes two Claw attacks.
  • Claw. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 8 (2d4 + 3) bludgeoning damage plus 7 (2d6) fire damage.
  • Molten Tail Slap (Recharge 4–6). The vorthropod unfurls its tail and slaps it down, showering the area with searing sparks and superheated rock. Each creature within 15 feet of it must make a DC 14 Dexterity saving throw, taking 28 (8d6) fire damage on a failed save, or half as much damage on a successful one.


This fiery tempered crustacean hides in lava flows, where the intense heat keeping its shell supple.

Vorthropods are large hard-shelled horrors with oversized foreclaws and muscular tails. These creatures come into existence as byproducts of residual energies and powerful magic drawn from the Elemental Planes of Fire, Earth, or Water.

Paradoxical Shells. When a vorthropod molts, instead of fully casting off the old shell, it instead fuses with nearby lava.

This creates a rocky, outer layer that requires the vorthropod to remain hot and submerged to be mobile, leaving the vorthropod’s hunting trips outside the lava short and rarely far from heat. While the creature sleeps, it remains motionless just beneath the surface of the lava, and the top of its shell, layered from years of cooled lava, is indistinguishable from a stepping stone. If the vorthropod stays out of lava for too long, its shell becomes so heavy and hard that eventually it encases the creature alive under a layer of basalt. When this happens, the vorthropod hibernates until lava softens its shell, but the vorthropod dies if it is forced to hibernate for too long.

Treacherous Steps. Though strong swimmers, climbers, and sprinters, vorthropods prefer to simply bask in heat and lava.

This makes them difficult to distinguish from tiny islands and safe footholds near volcanic activity. Touching one while crossing a lake of molten rock can easily lead to a fiery death—by lava or the vorthropod itself. Vorthropods typically start confrontations by slapping their tails, splashing lava and scattering hot stones, then they charge ahead in a superheated fury.

Section 15: Copyright Notice

Tome of Beasts 3 © 2022 Open Design LLC; Authors: Eytan Bernstein, Celeste Conowitch, Benjamin L. Eastman, Robert Fairbanks, Scott Gable, Basheer Ghouse, Richard Green, Jeremy Hochhalter, Jeff Lee, Christopher Lockey, Sarah Madsen, Ben Mcfarland, Jonathan Miley, Kelly Pawlik, Sebastian Rombach, Chelsea Steverson, Brian Suskind, Mike Welham

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