Recently while I was conducting a game session I found myself looking for a suitably impressive underground monster that could challenge my players in a dynamic and interesting battle. While many of options presented themselves I couldn’t settle on anything I particularly liked. This monster was created expressly to satisfy that need. The cinder wyrm is an underground ambush predator capable of devouring his foes and running off with his prey.
The great creature before you resembles a massive, jet-black snake with short clawed forelimbs and a long alligator-like mouth filled with razor-sharp teeth the size and shape of scimitars. Though the creature has no eyes, it moves with clear determination as it burst into and out of the earth, flames blasting from its horrible jaws.
CINDER WYRM CR 15
CE Gargantuan dragon
Init +4; Senses darkvision 120 ft., low-light vision, tremorsense 100 ft.; Perception +23
AC 30, touch 6, flat-footed 30 (+24 natural, –4 size)
hp 243 (18d12+126)
Fort +17, Ref +11, Will +13
Immune fire, paralysis, sleep
Speed 60 ft., burrow 60 ft.
Melee bite +26 (2d8+16/19-20/x3 plus grab), 2 claws +26 (2d6+11)
Space 20 ft.; Reach 15 ft. (20 ft. with bite)
Special Attacks lava breath weapon (100-ft. line, 15d8 fire damage and creatures are slowed for 1d4 rounds, Reflex DC 25 for half and negates the slowing effect, usable every 1d4 rounds), sudden ambush, superheated gas breath weapon (30-ft. cone, 15d8 fire damage and creatures are blinded for 1 round, DC 25 Reflex save for half and negates the blinding effect, usable every minute), swallow whole (10d6 fire damage, AC 22, 24 hp) , volcanic eruption
Str 32, Dex 11, Con 22, Int 13, Wis 14, Cha 19
Base Atk +18; CMB +33; CMD 43
Feats Critical Focus, Improved Critical (bite), Improved Initiative, Improved Vital Strike, Power Attack, Toughness, Vital Strike, Weapon Focus (bite, claw)
Skills Climb +32, Intimidate +25, Knowledge (dungeoneering) +22, Perception +23, Sense Motive +23, Survival +23, Use Magic Device 25
Languages Aklo, Draconic, Undercommon
SQ Powerful critical
Powerful Critical (Ex): The cinder wyrm’s bite attack has a x3 critical modifier.
Sudden Ambush (Ex): The cinder wyrm is especially skilled in ambushing its prey by bursting out of the ground. Whenever it makes a charge attack against a flat-footed opponent using its burrow speed, the cinder wyrm gains a +4 bonus to the attack roll instead of the normal +2 bonus. This bonus is also added to any attempt to grapple the target with its grab ability.
Swallow Whole (Ex): A character swallowed by the cinder wyrm is subject to its breath weapons and receives no saving throw to avoid the effects of the breath weapons. Additionally, whenever a character successfully cuts its way out of the cinder wyrm, the cinder wyrm regains the ability to swallow whole the next time it uses its lava breath weapon, as rapidly cooling lava fills any gaps left by cutting weapons.
Volcanic Eruption (Ex): A cinder wyrm can use its lava breath weapon while it is burrowing to create a column of molten rock directly above it, reaching to the surface. This column has a radius of 20 feet, and can be up to 100 feet tall (it cannot extend above the surface of the earth). Any character that enters or begins its turn in the area suffers 10d6 points of fire damage and is slowed. This lava cools rapidly and persists for 1d4 rounds. When the cinder wyrm uses this ability, it cannot use its lava breath weapon again for 1 minute.
Cinder wyrms are massive subterranean dragons that roam the endless deep cavern complexes below the surface. Creatures of ash and fire, cinder wyrms are most commonly found in areas with high levels of volcanism and commonly lair in massive, magma-filled chambers. Cinder wyrms are ambush hunters and apex predators who feed on the giant creatures that dwell in deep places, including giant magical beasts, vermin, oozes, and aberrations such as ropers and grey renders. Though normally content with eating such creatures and lording over their large territories, occasionally cinder wyrms find cause to roam about. Most often these wanderings are in search of treasure, particularly magic items which it can use to further its already considerable status.
Though in many ways a cinder wyrm’s behaviors mimic those of a common ambush predator, they are in fact exceptionally intelligent and cunning creatures. Comfortable in their own domains, they often employ networks of subterranean minions to guard the paths to its chamber, retrieve items of significance and value, and even conduct trade on the wyrm’s behalf. The cinder wyrm’s cunning extends to tactics, and in combat they prove devious and efficient fighters. They favor ambushing spellcasters to take them out of the fight as quickly as possible. They also favor devouring at least one opponent before using their breath weapons, to ensure that at least one enemy is helpless against their most devastating attacks.