Covered in black spikes, the dragon’s eyeless head swings from side to side. Darkness creeps from its strange, eel-like hide, spreading like ink in water.
Apex predators of the underworld, cave dragons are the stuff of nightmare for creatures with little else to fear. They can speak, but they value silence, speaking rarely except when bargaining for food.
Born to Darkness. Eyeless, these dragons have long, thin spikes that help them navigate tunnels, or seal passages around them, preventing foes from outflanking them. Their stunted wings are little more than feelers, useful in rushing down tunnels. Their narrow snouts poke into tight passages which their tongues scour free of bats and vermin. Young cave dragons and wyrmlings can fly, poorly, but older specimens lose the gift of flight entirely. Cave dragon coloration darkens with age, but it always provides good camouflage against stone: white like limestone, yellow, muddy brown, then black at adult and older categories. Mature adult and old cave dragons sometimes fade to gray again.
Ravenous Marauders. Cave dragons are always hungry and ready to eat absolutely everything. They devour undead, plant creatures, or anything organic. When feeding, they treat all nearby creatures as both a threat and the next course. What alliances they do make only last so long as their allies make themselves scarce when the dragon feeds. They can be bribed with food as easily as with gold, but other attempts at diplomacy typically end in failure. Cave dragons do form alliances with derro or drow, joining them in battle against the darakhul, but there is always a price to be paid in flesh, bone, and marrow. Wise allies keep a cave dragon well fed.
A Hard Life. Limited food underground makes truly ancient cave dragons almost unheard of. The eldest die of starvation after stripping their territory bare of prey. A few climb to the surface to feed, but their sensitivity to sunlight, earthbound movement, and lack of sight leave them at a terrible disadvantage.
Labyrinthine systems of tunnels, caverns, and chasms make up the world of cave dragons. They claim miles of cave networks as their own. Depending on the depth of their domain, some consider the surface world their territory as well, though they visit only to eliminate potential rivals.
Large vertical chimneys, just big enough to contain the beasts, make preferred ambush sites for young cave dragons. Their ruff spikes hold them in position until prey passes beneath.
Due to the scarcity of food in their subterranean world, a cave dragon’s hoard may consist largely of food sources: colonies of bats, enormous beetles, carcasses in various states of decay, a cavern infested with shriekers, and whatever else the dragon doesn’t immediately devour.
Cave dragons are especially fond of bones and items with strong taste or smell. Vast collections of bones, teeth, ivory, and the shells of huge insects litter their lairs, sorted or arranged like artful ossuaries.
Cave dragons have no permanent society. They gather occasionally to mate and to protect their eggs at certain spawning grounds. Large vertical chimneys are popular nesting sites.
There, the oldest cave dragons also retreat to die in peace. Stories claim that enormous treasures are heaped up in these ledges, abysses, and other inaccessible locations.
- The ceiling collapses above one creature that the dragon can see within 120 feet of it. The creature takes 10 (3d6) bludgeoning damage and is knocked prone and restrained (by fallen debris); damage is halved and the creature is not restrained if it makes a successful DC 15 Dexterity saving throw. The creature is freed when it or an adjacent ally uses an action to make a successful DC 15 Strength (Athletics) check.
- A ten foot-wide, ten foot-long crack opens in the cavern floor where the dragon wishes. Any creature occupying that space must make a successful DC 15 Dexterity saving throw or fall 20 feet, taking 7 (2d6) bludgeoning damage plus 7 (3d4) piercing damage from the jagged stones at the bottom.
- The dragon summons a swarm of insects as if it had cast insect plague, filling a 20-foot radius sphere within 90 feet of the dragon. Creatures that are in the affected space or that enter it take 22 (4d10) piercing damage, or half damage with a successful DC 18 Constitution saving throw. The swarm lasts until initiative count 20 on the next round.
The region containing a legendary cave dragon’s lair is warped by the dragon’s magic, which creates one or more of the following effects:
- Poisonous and odorless gases suddenly fill passages and caverns, and just as quickly disperse, within six miles of the dragon’s lair.
- Flash flooding turns tunnels into death traps as tremors create fissures in the stone within six miles of the lair. On the surface, ponds drain away, and long-dry creek beds break their banks in flood.
- Swarms of vermin within one mile of the lair increase in both size and number as they try to escape the dragon’s endless and undiscriminating hunger. If the dragon dies, these effects fade over the course of 1d10 days.
Tome of Beasts. Copyright 2016, Open Design; Authors Chris Harris, Dan Dillon, Rodrigo Garcia Carmona, and Wolfgang Baur.