AC 18 (natural armor)
HP 247 (15d20 + 90; bloodied 123)
Speed 50 ft., burrow 20 ft.
Proficiency +5; Maneuver DC 22
Skills Stealth +5 (+1d4)
Saving Throws Str +14, Con +11, Int +1, Wis +5, Cha +2
Senses blindsight 30 ft., tremorsense 60 ft., passive Perception 15
Languages —
Tunneler. The worm can tunnel through earth and solid rock, leaving behind a 10-foot-diameter tunnel.
Sand Cascade. When the worm emerges from under sand, each creature within 30 feet makes a DC 24 Constitution saving throw , falling prone on a failure.
ACTIONS
Multiattack. The worm attacks two different targets with its bite and its tail stinger.
Bite. Melee Weapon Attack: +14 to hit, reach 10 ft., one target. Hit: 25 (3d10 + 9) piercing damage. If the target is a Large or smaller creature, it makes a DC 19 Dexterity saving throw . On a failure, the target is swallowed. A swallowed creature is blinded and restrained , it has total cover from attacks from outside the worm, and it takes 24 (7d6) acid damage at the start of each of the worm’s turns.
If a swallowed creature deals 35 or more damage to the worm in a single turn, or if the worm dies, the worm vomits up all swallowed creatures.
Tail Stinger. Melee Weapon Attack: +14 to hit, reach 10 ft., one creature. Hit: 19 (3d6 + 9) piercing damage, and the target makes a DC 19 Constitution saving throw , taking 42 (12d6) poison damage on a failed save or half damage on a success.
REACTIONS
Fighting Retreat. When a creature makes an opportunity attack on the worm, the worm attacks with either its bite or its tail stinger.
Combat
The worm usually attacks the foe that makes the most noise, though it may also try to swallow a creature that badly injures it. If attacked from one end while in one of its narrow tunnels, it burrows in a tight circle so it can attack with both its bite and stinger. In melee, it retreats and advances in order to get both its attacks in play and to make use of its Fighting Retreat reaction.
Dun-colored sand worms burrow through desert dunes, leaving behind no tunnel or trace of their passing. They lurk just below the surface of the sand, rearing up to attack passing creatures.
1 About to burst through the wall or ground to attack
2 Excavating a nearby tunnel
3 Crawling through existing corridors and wide caverns, or along the surface of the earth, occasionally rearing up to look for prey
4 Motionless, listening for prey
1 A smooth-walled circular tunnel, 10 feet wide
2 The vibration of grinding stone, getting louder
3 A path of disturbed ground, as if something was tunneling underneath
4 A sinkhole that drops into a worm tunnel
Purple worms are a danger to creatures in underground caverns, and occasionally emerge above ground in rocky areas. Ice worms traverse the tundra and sand worms lurk under dunes.
CR 11–16 Purple worm , ice worm , or sand worm
Treasure diamond (5,000 gp)
CR 23–30 2 purple worms , ice worms , or sand worms
Treasure 2 emeralds (5,000 gp each), 3 rubies (5,000 gp each)