Root Behemoth

Gargantuan elemental, neutral

Armor Class 20 (natural armor)
Hit Points 280 (16d20 + 126)
Speed 50 ft., burrow 50 ft.

30 (+10) 15 (+2) 25 (+7) 2 (-4) 19 (+4) 12 (+1)

Saving Throws Str +16, Con +13, Wis +10
Skills Perception +14, Stealth +8
Damage Resistances acid; bludgeoning, slashing, and piercing from nonmagical attacks
Damage Immunities poison
Condition Immunities charmed, petrified, poisoned
Senses darkvision 60 ft., tremorsense 60 ft., passive Perception 24
Challenge 20 (25,000 XP)
Proficiency Bonus +6


  • Earth Glide. The behemoth can burrow through nonmagical, unworked earth and stone. While doing so, the behemoth doesn’t disturb the material it moves through.
  • Legendary Resistance (3/Day). If the behemoth fails a saving throw, it can choose to succeed instead.
  • Regeneration. The behemoth regains 20 hit points at the start of its turn. If it takes thunder damage, this trait doesn’t function at the start of the behemoth’s next turn. The behemoth dies only if it starts its turn with 0 hit points and doesn’t regenerate.
  • Siege Monster. The behemoth deals double damage to objects and structures.
  • Unique Anatomy. The behemoth doesn’t require air, food, drink, or sleep.


  • Multiattack. The behemoth makes three Slam attacks.
  • Slam. Melee Weapon Attack: +16 to hit, reach 10 ft., one target. Hit: 28 (4d8 + 10) bludgeoning damage.
  • Stone Toss. Ranged Weapon Attack: +16 to hit, range 90/360 ft., up to two targets. Hit: 43 (6d10 + 10) bludgeoning damage.
  • Elemental Kick (1/Day). The behemoth kicks some dirt toward an unoccupied space within 60 feet of it that it can see. An earth elemental appears in that space. It acts an ally to the behemoth and takes its turn immediately after it. The elemental lasts for 1 hour, until it or the behemoth dies, or until the behemoth dismisses it as a bonus action.
  • Shower of Stone (Recharges 5-6). The behemoth extends its body into the ground, disrupts the earth, and causes stone to shower on its enemies. Each creature within 60 feet of the behemoth must make a DC 21 Constitution saving throw, taking 77 (14d10) bludgeoning damage on a failed save, or half as much damage on a successful one.
  • Stone Gaze (1/Day). The behemoth stares deep into the soul of its enemies. The behemoth targets a creature that it can see within 60 feet of it. The target is petrified and must make a DC 21 Constitution saving throw at the end of each of its turns until it has two successes or two failures. On two successes, the effect ends. On two failures, the effect becomes permanent. The greater restoration spell and similar magic that can undo petrification have no effect on a petrified creature unless the behemoth is dead, in which case the magic works normally, freeing the petrified creature as well as ending the petrified condition on it.


Root behemoths enjoy the feeling of drifting through dirt and rock. Left alone, most root behemoths would swim through stone for hours at a time. Root behemoths do not understand that their movement causes disruptions in the world around them.

When root behemoths detect the presence of others of their kind in the same area, they can gather to create a barrage. Barrages of root behemoths can cause extinctionlevel events if they aren’t stopped. Deities sometimes get involved to decrease the impact of a barrage.

A Barrage of Root Behemoths’ Lair

Barrages lair deep underground in caves made from their own activity. There are typically no ways to the surface from a barrage’s lair unless the barrage breaks into a neighboring cave system.

A barrage often accidentally gathers large amounts of precious metal or gemstones while gliding through its territory. In rare instances, a barrage gathers things foreign to it, including magical items or even artifacts.

Lair Actions

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

Join the Chorus. The barrage summons a swarm of earth elementals that appear in unoccupied spaces within the lair. The swarm obeys the barrage’s commands, takes its turn on initiative count 10 (losing initiative ties), and fights until destroyed. The barrage can’t use this effect again until it finishes a long rest.

Pillar of Stone. Stone erupts from a point on the ground the barrage can see within 120 feet of it, creating a 20-foothigh, 5-foot radius column. Each creature in the column’s area must make a DC 15 Constitution saving throw, taking 35 (10d6) bludgeoning damage on a failed save, or half as much damage on a successful one.

Sand Trap. A 20-foot radius area within the barrage’s lair becomes soft before hardening. Any creature on the ground in the area must succeed at a DC 15 Dexterity saving throw or become restrained. A creature can take an action to make a DC 15 Strength check, ending the effect on itself or another creature within its reach on a success.

Steam Burst. The barrage breaks open a vent of steam underground with a violent tremor. The lair becomes heavily obscured until initiative count 20 on the next round. Each creature other than the barrage on the ground in the area must succeed on a DC 15 Strength or Dexterity saving throw (target’s choice) or be knocked prone.

Regional Effects

The region surrounding the lair of a barrage is warped by the barrage’s presence and worsens over time, creating the following effects:

Growing Tremors. Tremors occur within 20 miles of the barrage’s location every 6 hours, each lasting 1 minute.

After the first tremor, damage is minor. After 3 days, the tremors become strong enough to destroy temporary structures. After 6 days, they become strong enough to destroy most standard structures. After 10 days, they become strong enough to destroy reinforced structures.

Like Home. Rocky fissures within 1 mile of the barrage’s lair form portals to the Elemental Plane of Earth enabling its native creatures to pass through and dwell on the plane of the lair.

Overgrowth. The area on the surface above the barrage’s lair becomes a lush forest in a 6-mile radius. Beasts within this forest become fiercely territorial, defending the forest against any intruders. If the barrage is destroyed, these effects fade over the course of 1d10 days.


In the deepest, lushest forests of the Elemental Plane of Earth, there are creatures beyond understanding. These beings have infinite forms incomprehensible to mortal eyes, but the mind conjures images of gigantic wolves made of tangled greenery and roots. The few mortals who have seen these creatures and lived to tell the tale have called them root behemoths.

Playful but Deadly. Root behemoths find creatures not made up of rocks and plant matter to be intriguing. The root behemoths do not understand that their explorations of these creatures can be fatal. If a root behemoth sees something it has never seen before, it investigates, and that can lead to disastrous results.

Force of Nature. The most terrible quakes and volcanic eruptions on the Material Plane are often the result of a root behemoth making its way out of its native plane.

Individual root behemoths panic in such a situation, creating devastating impacts on the environment around it.

Always Underfoot. Because root behemoths live underground and sometimes travel without surfacing, one could be lying below with those above completely unaware.

A whole barrage of root behemoths tends to be noticeable though as its lair affects the surrounding area. Nonetheless, those who burrow or travel below the surface may be surprised to come face to face with one of these massive creatures or an entire barrage of them.

Accidentally Worshipped. Root behemoths are so expansive that mortals often mistake them for gods.

There are tales of cults that try to follow these majestic creatures or to deliberately put themselves in the path of one. Some don’t survive the encounter, but the surviving cult members simply blame it on the will of their gods.

Groups that worship root behemoths look for their tracks or other evidence that they have been there. If any signs are discovered, it is seen as a blessing for the first to spot them.

Section 15: Copyright Notice

Affinity Torus Copyright 2022 Dias Ex Machina Author Chris Dias

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