Rare N Gargantuan Beast Fire
Senses Perception +25; darkvision, tremorsense (imprecise) 100 feet
Skills Athletics +38
Str +10, Dex -1, Con +9, Int -3, Wis -1, Cha -1
AC 40; Fort +36, Ref +25, Will +27
HP 410; fire Healing; Immunities fire; Weaknesses cold 15
Fire Healing As long as a crimson worm is in contact with a fire or body of magma at least as large as itself, it gains fast Healing 20. When struck by a magical fire effect from anything other than itself, a crimson worm regains Hit Points equal to half the fire damage the effect would otherwise deal.
Inexorable As purple worm.
Shake It Off As purple worm.
Speed 40 feet, burrow 40 feet, swim 20 feet
Melee jaws +36 (deadly 3d10, fire, reach 20 feet), Damage 3d10+18 piercing plus 2d6 fire and Improved Grab
Melee stinger +36 (agile, fire, poison, reach 20 feet), Damage 2d12+18 piercing plus 2d6 fire and crimson worm venom
Melee body +34 (fire, reach 15 feet), Damage 2d10+16 bludgeoning plus 2d6 fire
Breath Weapon (evocation, fire, primal) The crimson worm breathes a blast of flame in a 60-foot cone that deals 18d6 fire damage to all creatures in the area (DC 41 basic Reflex save). It can't use Breath Weapon again for 1d4 rounds.
Crimson Worm Venom (poison); Saving Throw DC 41 Fortitude, Maximum Duration 6 rounds; Stage 1 1d6 poison damage and drained 1 (1 round), Stage 2 2d6 poison damage and drained 1 (1 round); Stage 3 2d6 poison damage and drained 2 (1 round).
Fast Swallow Trigger The worm Grabs a creature. Effect The worm uses Swallow Whole.
Rock Tunneler As purple worm.
Swallow Whole Huge, 3d10+10 bludgeoning plus 2d6 fire, Rupture 36
Thrash As purple worm.
Among the most dangerous cave worms are the fiery crimson worms. In addition to being even larger than azure or purple worms, the crimson worm has a penchant for burrowing through volcanic regions that, over the generations, have infused it with a supernatural link to the Elemental Plane of Fire. The molten heart of an active volcano is an attractive lair for a crimson worm, as are the sprawling fields of bubbling magma found in the deepest reaches of the underworld. Legends from ancient peoples, precursor dwarven societies, and colonists of the Elemental Planes populated moats of lava with crimson worms likely have some basis in truth, although the methods such ancients used to keep these " moat worms” contained and prevented them from chewing their way through fortress foundations must have been significant.
Crimson worms sometimes frequent areas on the surface where volcanism creates hot springs or other geothermal features, but even then they prefer to spend most of their time burrowing through the ground in their never-ending search for sustenance. Surface lands claimed by crimson worms are notable for the mound-shaped burrows these creatures leave behind as they dig.
Some societies view the immense cave worms as natural disasters or incarnations of wrathful gods. Cave worms that have been active in a region often become part of that area's local lore.