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Purple Worm

• Size: Gargantuan
• Type: Monstrosity
• Alignment: Unaligned
• AC: 18
• Initiative: -1 (9)
• HP: 247 (15d20+90)
• Speed: 50 ft, Burrow 30 ft.

ATTR	VAL	MOD	SAVE
STR	28	+9	+15
DEX	7	-2	-2
CON	22	+6	+12
INT	1	-5	-5
WIS	8	-1	-1
CHA	4	-3	-3

• Senses: Blindsight 30 ft., Tremorsense 60 ft.; Passive Perception 9
• Languages: None
• CR: 15 (XP 13,000; PB +5)

Traits

Tunneler. The worm can burrow through solid rock at half its burrow speed and leaves a 10-foot-diameter tunnel in its wake.

Actions

Multiattack. The worm makes two attacks, using Bite, Tail Stinger, or both.

Bite. Melee Attack Roll: +14, reach 10 ft. Hit: 22 (3d8+9) Piercing damage. If the target is a Large or smaller creature, it must succeed on a DC 19 Dexterity saving throw or be swallowed by the worm. A swallowed creature has the Blinded and Restrained conditions, has total cover against attacks and other effects outside the worm, and takes 21 (6d6) Acid damage at the start of each of the worm's turns. If the worm takes 30 or more damage on a single turn from a swallowed creature, the worm must succeed on a DC 21 Constitution saving throw at the end of that turn or regurgitate the creature, which falls prone in a space within 10 feet of the worm. If the worm dies, a swallowed creature is no longer restrained by it and can escape from the corpse by using 20 feet of movement, exiting prone.

Tail Stinger. Melee Attack Roll: +14, reach 10 ft. Hit: 19 (3d6+9) Piercing damage plus 42 (12d6) Poison damage. Constitution Saving Throw: DC 19. Failure: The target has the Poisoned condition for 1 minute. The target repeats the save at the end of each of its turns, ending the effect on itself on a success.

Lore & Background

Purple worms are colossal burrowing creatures that represent one of the most feared predators of the deep earth. These massive annelids can grow to incredible lengths and possess the ability to tunnel through solid rock with ease, creating vast underground networks as they hunt for prey. Purple worms are ancient creatures that have existed since the dawn of time, and their presence often indicates deep, primordial connections to the earth itself.

These creatures are driven by an insatiable hunger and will consume virtually anything they encounter, from other underground creatures to unfortunate surface dwellers who venture too deep. Their massive size and burrowing abilities make them capable of reshaping entire underground ecosystems.

Combat Tactics

Purple worms use their massive size and burrowing ability to their advantage, often attacking from below by bursting through the ground. They attempt to swallow smaller creatures whole while using their stinger to poison larger threats that they cannot immediately consume.

Encounter Ideas

Underground Terror: A purple worm threatens a mining operation or underground settlement. Tunnel Network: Heroes must navigate tunnels created by a purple worm to reach their destination. Ancient Predator: A purple worm awakens from centuries of dormancy and begins hunting. Ecosystem Threat: A purple worm's presence is disrupting the balance of an underground realm.

Environmental Effects

Purple worm activity creates extensive tunnel networks and can cause surface collapses. Their presence drives other underground creatures to flee or adapt to the new tunnel systems they create.

Treasure

Purple worms don't intentionally collect treasure, but their digestive systems often contain valuable items from their many meals, including gems, metals, and magical items that have resisted digestion.

Plot Hooks

The Deep Hunt: Heroes must track a purple worm through its tunnel network to stop its rampage. Geological Survey: A purple worm's tunnels have revealed ancient ruins or mineral deposits. Symbiotic Relationship: Other creatures have learned to follow purple worms to scavenge their leftovers. Primordial Guardian: A purple worm protects an ancient underground location or artifact.

Lore & Background

Purple worms are colossal subterranean predators that tunnel through solid rock with the same ease others move through water. These massive creatures, reaching lengths of over 80 feet, are among the most feared denizens of the deep earth. Their insatiable hunger drives them to consume everything in their path - rock, metal, and flesh alike - making them both apex predators and geological forces.

These ancient creatures predate most civilizations, and their tunneling activities have shaped underground landscapes for millennia. Dwarven miners speak in hushed tones of purple worm sign, while deep-dwelling peoples like drow and duergar have learned to read the tremors that herald their approach. The creature's purple-hued hide is incredibly tough, and its massive gullet can swallow entire groups of adventurers whole.

Combat Tactics

Purple worms are devastating combatants that rely on their immense size and powerful attacks. They use their tremorsense to detect prey from great distances, often bursting through stone walls or floors to surprise enemies. Their bite attack can swallow humanoid-sized creatures whole, while their venomous stinger tail can poison and kill even the hardiest warriors.

In combat, purple worms are relentless, pursuing prey with single-minded determination. They use their tunneling ability to disappear into solid stone, only to emerge elsewhere on the battlefield. Their massive size allows them to attack multiple enemies simultaneously, and they show no tactical subtlety - only overwhelming force and primal hunger.

Encounter Ideas

1. The Trembling Deep Mining operations have awakened a purple worm, and its movements threaten to collapse an entire underground city. The party must either find a way to redirect the creature or eliminate it before thousands of lives are lost to cave-ins and direct attacks.

2. Tunnel Chase While exploring ancient dwarven ruins, the party's presence attracts a purple worm that begins hunting them through the tunnel network. The chase becomes a deadly game of cat and mouse as the creature can move through solid stone while the party is confined to existing passages.

3. The Great Excavation A purple worm's natural tunneling has accidentally breached a sealed chamber containing ancient evils. The party must deal with both the unleashed threats and the creature responsible, all while preventing further structural damage to the underground complex.

4. Worm Rider Cult A fanatical group has learned to communicate with and partially control a purple worm, using it as both a weapon and a means of creating their underground domain. The party must infiltrate the cult's operation and find a way to break their hold over the massive creature.

Environmental Effects

• Seismic Activity: Purple worm movement causes tremors that can knock creatures prone and trigger cave-ins
• Tunnel Networks: Abandoned purple worm tunnels create new passages but may be unstable and prone to collapse
• Acidic Secretions: The creature's digestive acids seep into surrounding stone, weakening structural integrity
• Disturbed Ecosystems: Purple worm activity displaces other underground creatures, creating refugee populations and territorial conflicts

Treasure

• Undigested Wealth (2000-8000 gp): Coins, gems, and metal objects that survived the creature's digestive process
• Purple Worm Hide (5000 gp): Incredibly tough hide suitable for crafting magical armor with acid resistance
• Crystallized Venom (1000-3000 gp): Concentrated poison from the creature's stinger, valuable to alchemists
• Ancient Artifacts (varies): Items from civilizations the worm has devoured, potentially including magical weapons or historical treasures
• Geological Samples (500-2000 gp): Rare minerals and gems collected during the creature's extensive tunneling

Plot Hooks

1. The Lost Expedition A wealthy mining consortium's expedition disappeared in purple worm territory, along with maps to a legendary gemstone deposit. The party must brave the creature's domain to recover the maps and discover the fate of the missing miners.

2. Seismic Weapon A mad wizard seeks to control a purple worm and use its tunneling abilities to undermine enemy fortifications. The party must stop this living siege engine before it can be turned against innocent cities and kingdoms.

3. The Hollow Mountain An entire mountain has been hollowed out by purple worm activity, creating a massive underground cavern system. Various factions seek to claim this space, but the original tenant still lurks in the deepest tunnels, protecting its territory.

4. Digestive Archaeology Scholars believe a purple worm has consumed artifacts from a lost civilization, and they need brave souls to track the creature and recover the historical treasures from its digestive system before they're completely dissolved by acid.