Vault-Crawler

A vault-crawler is a big insect that looks like a cross between an ant and a spider, its long body armored in brown-to-yellow mottled chitin. Swollen, glowing eyes overhang mandibles big enough to bite a wyrmkin in two, and its front limbs are edged like blades. Sticky barbs on every foot let it walk walls and ceilings as easily as floors.

Wild vault-crawlers and the trained mounts of the undead dragon king's elite templars are physically identical; only saddles and riders tell them apart, and the riders are every bit as nasty as their steeds.

Each round a vault-crawler slashes twice with its forelimbs, sword-fashion, for 1d10 apiece, and bites for 2d6. A successful bite also traps the victim in its jaws, squeezing for another 1d6 each round. From the next round on, both blades hit a held victim automatically (damage is rolled, no attack roll) until the victim breaks loose with a successful open doors roll or dies.

The creature ignores other attackers while finishing its catch, only dropping it to defend itself once reduced below half its hit points. Its thorax spins a sticky line, spider-style, for dropping from a ceiling; riders use this to ambush foes (-2 to their surprise rolls), and a mount and rider that land hits from above with surprise inflict double damage that first round. Prepared riders who hold on can stay mounted on walls and ceilings and are trained to go wherever the beast chooses.

The dragon king's people discovered vault-crawlers already infesting the under-region upon arriving. Aggressive but less chaotic than the wall-walkers of the fire-caverns, they nonetheless war with them over food and territory. The templars tamed about 100 as mounts, and many more wild ones roam the surrounding tunnels.

Wild vault-crawlers are solitary, wandering hunters that build nests only for laying, pairing off only until their brood emerges, after which parents and young scatter. The tame ones barely tolerate each other, so their pens keep them apart to limit attacks. They mature in as little as six months and live about five years.

Vault-crawlers eat meat, hunting it themselves or receiving daily rations if tame. Each female lays once a year, about 10 young per season; the eggs hatch in three months, guarded by the male throughout. Second-generation wyrmkin shape armor, weapons and tools from the chitin, but rarely kill for it, preferring dead mounts or wild crawlers found expired in the tunnels.

These riders are the dragon king's best troops. They patrol the ceilings of the buried city watching the streets below, and citizens loathe them because the mounts are so vicious; a vault-crawler may tear the arm off a passing wyrmkin for no reason, and even its rider struggles to rein in its bloodlust. Four squadrons of 25 currently exist, earmarked to spearhead the coming assault on the surface and given the pick of the king's magical arsenal.

Riders are 5th-level templars in enchanted vault-crawler hide, carrying magical weapons (often a long sword +1), metal arms, or weapons made from their mounts' limbs. Officers are 8th-level templars with metal weapons enchanted up to +3. Every squadron also includes a life-draining wizard (level 1d6+6, so 7th-10th) from a sorcerous college, bearing five random magical items; reroll anything excessively powerful.

Mount and rider train as a team, so both may attack the same foe in a round, and their savage, relentless style earns them +2 on initiative.