Ancient Lindworm
Gargantuan dragon, Neutral Evil
Armor Class 19 (natural armor)
Hit Points 297 (18d20 + 108)
Speed 50 ft., burrow 30 ft., swim 50 ft.
STR 26 (+8) · DEX 14 (+2) · CON 22 (+6) · INT 18 (+4) · WIS 20 (+5) · CHA 16 (+3)
Skills Deception +8, Perception +10, Stealth +7, Survival +10
Senses Blindsight 60 ft., Truesight 60 ft., Darkvision 120 ft., passive Perception 20
Languages Common, Draconic, Primordial, Telepathy 120 ft.
Challenge 15 (13,000 XP)
Traits
Amphibious. The lindworm can breathe air and water.
Legendary Resistance (3/Day). If the lindworm fails a saving throw, it can choose to succeed instead.
Magic Resistance. The lindworm has Advantage on saving throws against spells and magical effects.
Noon Torpor. Despite its usual resilience, at exactly high noon each day, the lindworm falls into a deep, supernatural sleep for 15 minutes. It gains the Unconscious condition during this time. The effect ends early only if the lindworm takes damage.
Noxious Aura. A creature that starts its turn within 15 feet of the lindworm takes 10 (3d6) poison damage.
Rapid Regeneration. The lindworm regains 20 hit points at the start of its turn if it has at least 1 hit point. If the lindworm takes radiant damage or is in direct sunlight, this trait doesn't function at the start of its next turn.
Actions
Multiattack. The lindworm makes three attacks: one with its Bite or Constrict, and two with its Claws. It can replace one attack with Spellcasting.
Bite. Melee Attack: +13 to hit, reach 15 ft., one target. Hit: 24 (3d10 + 8) piercing damage plus 14 (4d6) acid damage.
Claw. Melee Attack: +13 to hit, reach 10 ft., one target. Hit: 18 (3d6 + 8) slashing damage.
Constrict. Melee Attack: +13 to hit, reach 15 ft., one Large or smaller creature. Hit: 26 (4d8 + 8) bludgeoning damage, and the target is Grappled (escape DC 21). Until this grapple ends, the creature is Restrained, takes 14 (4d6) bludgeoning damage plus 10 (3d6) poison damage at the start of each of the lindworm's turns, and the lindworm can't constrict another target.
Poison Breath (Recharge 5-6). The lindworm exhales an incredibly toxic, corrosive mist in a 60-foot cone. Each creature in that area must make a DC 19 Constitution saving throw, taking 45 (10d8) poison damage and 18 (4d8) acid damage on a failed save, or half as much damage on a successful one.
Spellcasting.
At Will: Detect Magic (PHB, p. 262), Speak with Animals (PHB, p. 318)
1/Day Each: Cloudkill (PHB, p. 251), Scrying (PHB, p. 313), Legend Lore (PHB, p. 290)
Bonus Actions
Tail Whip. Melee Attack: +13 to hit, reach 20 ft., one target. Hit: 17 (2d8 + 8) bludgeoning damage, and the target is automatically knocked Prone.
Reactions
Corrosive Blood. When the lindworm takes piercing or slashing damage from a creature within 10 feet of it, caustic blood sprays outward. The attacker takes 14 (4d6) acid damage and is automatically Poisoned until the end of its next turn.
Lore
An ancient, wingless dragon-serpent.
The lindworm—also spelled lindwurm or lindorm—is one of the oldest dragon species found in old European and Nordic folktales. Its very name, going back to ancient Germanic and Scandinavian tongues, means simply “serpent,” “flexible one,” or “crawling beast” and was used strictly for gigantic snake-like dragons that kill by coiling around and crushing their prey.
Forget the picture of a classic sky-soaring dragon with vast wings: a lindworm looks nothing like that. Think instead of a colossal, almost unbelievably large serpent with a long, muscular body. It has no wings at all and, in most versions, only two forelegs tipped with enormous claws. It moves by slithering on its belly while digging those claws into the ground for traction. Swedish folklore sometimes makes it even more nightmarish—completely limbless, like a gargantuan worm, either pitch-black or a blinding, icy white.
From Grimm Legends Bestiary 5E, p. 44 · Fern Flower Press