Primordial Matriarch

Family: Primordial

Gargantuan elemental, neutral

Armor Class 20
Hit Points 313 (19d20 + 114)
Speed 0 ft., fly 120 ft. (hover)

18 (+4) 30 (+10) 23 (+6) 10 (+0) 21 (+5) 18 (+4)

Saving Throws Str +11, Wis +12, Cha +11
Damage Resistances acid, cold, fire, lightning, thunder; bludgeoning, piercing, and slashing from nonmagical attacks
Damage Immunities poison
Condition Immunities exhaustion, grappled, paralyzed, petrified, poisoned, prone, restrained, unconscious
Senses blindsight 120 ft. (blind beyond this radius), passive Perception 15
Languages Primordial
Challenge 21 (33,000 XP)
Proficiency Bonus +7


  • Elemental Attacks. The primordial matriarch’s weapon attacks are magical. When she hits with any weapon, the weapon deals an extra 5d6 damage of the type determined by Roiling Elements.
  • Elemental Aura. At the start of each of the primordial matriarch’s turns, each creature within 5 feet of her takes 10 (3d6) damage of the type determined by Roiling Elements. A creature that touches the primordial matriarch or hits her with a melee attack while within 10 feet of her takes 10 (3d6) damage of the type determined by Roiling Elements. A nonmagical weapon that hits the matriarch is destroyed after dealing damage.
  • Elemental Nature. The primordial matriarch doesn’t require air, food, drink or sleep.
  • Legendary Resistance (3/Day). If the primordial matriarch fails a saving throw, she can choose to succeed instead.
  • Magic Resistance. The primordial matriarch has advantage on saving throws against spells and other magical effects.
  • Roiling Elements. At the start of each of her turns, the primordial matriarch chooses one of the following damage types: acid, cold, fire, lightning, or thunder. The matriarch has immunity to that damage type until the start of her next turn.
  • Siege Monster. The primordial matriarch deals double damage to objects and structures.


  • Multiattack. The elemental matriarch uses Storm Blast. She then makes two Elemental Lash attacks.
  • Elemental Lash. Melee Weapon Attack: +17 to hit, reach 15 ft., one target. Hit: 32 (4d10 + 10) bludgeoning damage plus 17 (5d6) damage of the type determined by Roiling Elements.
  • Storm Blast. The primordial matriarch emits elemental energy in a 90-foot cone. Each creature in the area must make a DC 20 Dexterity saving throw. On a failure, a creature takes 21 (6d6) damage of the type determined by Roiling Elements and suffers one of the following effects, depending on the damage type. On a success, a creature takes half the damage and doesn’t suffer an additional effect, unless specified below.
  • Acid Blast. On a failed save, the creature is covered in acid. At the start of each of its turns, it takes 7 (2d6) acid damage until it or another creature takes an action to scrape or wash off the acid.
  • Cold Blast. On a failed save, the creature is restrained by ice until the end of its next turn, or until it or another creature takes an action to break it free. On a successful save, the creature’s speed is reduced by 10 feet until the end of its next turn.
  • Fire Blast. On a failed save, the creature catches fire. Until it or another creature takes an action to douse the fire, the creature takes 7 (2d6) fire damage at the start of each of its turns.
  • Lightning Blast. On a failed save, the creature is incapacitated until the end of its next turn. On a successful save, the creature can’t take reactions until the start of its next turn.
  • Thunder Blast. On a failed save, the creature is deafened for 1 minute. At the end of each of its turns, a deafened creature can repeat the saving throw, ending the deafness on itself on a success. On a successful save, the creature is deafened until the end of its next turn.
  • Create Elementals. The primordial matriarch magically creates up to 3d6 mephits, 2 air, earth, fire, or water elementals, 2 ice elementals, or 1 rockslide elemental. The Elementals arrive at the start of her next turn, acting as allies of the matriarch and obeying her spoken commands. The Elementals remain for 1 hour, until the matriarch dies, or until the matriarch dismisses them as a bonus action. The primordial matriarch can have any number of Elementals under her control at one time, provided the combined total CR of the Elementals is no higher than 10.


  • Elemental Adaptation. When the matriarch would take acid, cold, fire, lightning, or thunder damage, she can change the element selected with Roiling Elements to that type of damage, gaining immunity to that damage type, including the triggering damage.


The primordial matriarch’s lair is the mountain peak where it create new elementals. It remains only until she has deemed there are enough new elementals to renew the balance on her current plane—or until the mountain is reduced to nothing.

On initiative count 20 (losing initiative ties), the primordial matriarch takes a lair action to cause one of the following effects; the primordial matriarch can’t use the same effect two rounds in a row:

  • Consume. The matriarch chooses a point on the ground she can see within 30 feet of her. The ground partially dissolves into her form, restoring 21 (6d6) hp to the matriarch. The ground within 10 feet of that point then becomes difficult terrain.
  • Rock Fall. The matriarch chooses a point on a rockface or the ground within 120 feet of her. Rocks tumble down or roll forward from that point in a 60-foot line that is 10 feet wide. Each creature in that line must succeed on a DC 20 Dexterity saving throw or take 18 (4d8) bludgeoning damage and be forced prone.
  • Tremor. The terrain within 60 feet of the matriarch rumbles. Each creature standing on the ground in that area must succeed on a DC 20 Dexterity saving throw or be forced prone and incapacitated until the end of its next turn.


While the presence of a primordial matriarch is already a catastrophe, her surging, elemental power also creates one or more of the following effects:

  • Cacophony. Within 1 mile of the matriarch’s mountaintop, the thunderous noise of her presence and the resulting destruction is obvious. Animals flee the area in a panic, and do not return until the matriarch is gone.
  • Empowered Elementals. Elementals within 5 miles of a primordial matriarch have advantage on up to three saving throws each day.
  • Erratic Weather. The area within 10 miles of a primordial matriarch’s mountain suffers from frequent weather changes. These weather events are violent and often unseasonal, but they rarely last more than 1 hour. If the primordial matriarch dies, these effects fade over the course of 1d10 days.


The primordial matriarch can take 3 legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature’s turn. The matriarch regains spent legendary actions at the start of her turn.

  • Elemental Change. The primordial matriarch changes the damage immunity granted by Roiling Elements.
  • Fly. The primordial matriarch flies up to half her flying speed without provoking opportunity attacks.
  • Create Elemental (Costs 2 Actions). The primordial matriarch uses Create Elementals.
  • Return to Mother (Costs 3 Actions). The primordial matriarch absorbs an Elemental within 10 feet of her, gaining a temporary hp equal to 10 times the CR of the Elemental absorbed.


The massive living storm contorts with writhing, intertwined bands of elemental power. With each crack of thunder, lesser elementals emerge from the maelstrom.

This primordial contains equal parts of all four classical elements, a roiling mass that shifts quickly from fire to water, crackling storm clouds to roiling dust, equally all of them at once. Though not impervious to them all, the matriarch can choose one dominant element, depending on the circumstances, to protect herself against such attacks.

Planar Visitors. Primordial matriarchs exist primarily in the Elemental Planes, continuously drifting from one to another. The mass destruction of elementals in a short time span causes an unbalance in the natural world, attracting a matriarch to other planes.

Prime Elemental. Because a matriarch is a powerful, creative elemental force, lesser elementals follow her commands without question. Even mighty elemental beings like the primordial surge or storm lord defer to a matriarch’s will.

Mountain Eater. On the Material Plane, a primordial matriarch is most often found in mountainous regions. She settles atop a high peak and devours the entire mountain, over time, to fuel herself as she produces more elementals. Only her destruction or the renewed balance of the plane’s elementals stops a matriarch or convinces her to move on to another plane.

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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