Ancient Blue Greatwyrm

Ancient blue greatwyrms make their lairs in deserts, barren places, and other arid landscapes. They prefer warm climates, but if an otherwise ideal potential lair presents itself in a cold environment, they find ways to adapt.

Instead of seeking out lofty domiciles, ancient blue greatwyrms build their lairs by using their lightning breath and their burrowing ability to carve out crystallized caverns, intricate warrens of rooms, and tunnels that can be expanded to accommodate a growing family. Most of its floors are loosely packed sand, with patches of rough stone showing through in some areas. The greatwyrm has constructed a system of mirrors to bring in sunlight from chambers open to the sky, a system that not only brightly lights the interior but also heats the sand to a comfortable basking temperature. Still, they appreciate the tactical advantages of height and usually create their lairs near a spire or cliff from which they can keep watch over their territory.

Thunderstorms rage around an ancient blue greatwyrm's lair, and narrow tubes lined with glassy sand ventilate the lair, all the while avoiding the deadly sinkholes that are the greatwyrm's first line of defense. An ancient blue greatwyrm will collapse the caverns that make up its lair if that lair is invaded. The greatwyrm then burrows out, leaving its attackers to be crushed and suffocated. When it returns later, it collects its possessions — along with the wealth of the dead intruders.

Though most ancient blue greatwyrms would be loath to use the term themselves, their lairs are often surprisingly homey. They favor lairs that balance beauty and comfort and adorn them in soothing shades of blue, purple, and green.

Ancient Blue Greatwyrm Lair Features

The lair has the following features:

Entrance Chamber. An open central cavern is the lair’s primary entrance. The glass walls rise 30 feet to the surface and are fused with carved stone pillars and partial walls from the ancient city. A narrow, jagged piece of granite juts out horizontally from the wall near the top of the chamber, providing a perch from which the greatwyrm can survey the cavern. The sand covering the floor of the chamber sometimes ripples or swirls ominously, perhaps in response to unpredictable desert winds, the greatwyrm's magic, or some creature lurking beneath the sand.

Hoard Display. Just off the entrance chamber, a smaller cavern with a worked stone floor contains the greatwyrm's artfully arranged hoard. The glass walls of this chamber are studded with blue gems, and narrow light wells let in sunlight that bathes the room in dappled blue light. The ancient stone tiles on the floor contain lightning-charged traps to blast intruders.

Greatwyrm's Den. The greatwyrm sleeps in a large chamber. The den is a well-preserved remnant of the ancient city; this gracious, elegant space is hung with silk curtains in shades of blue and purple, and its worked-stone floor is covered with plush, patterned rugs in complementary hues. It features a bejeweled and cushioned dais on which the greatwyrm often reclines.

Private Entrance. Just above and to the right of the den is a small chamber open to the sky that the greatwyrm uses as a private entrance to the lair. A secret door prevents unwitting creatures from wandering directly into the den.

Treasury. At the left end of the den, a door set under a blue-tiled arch leads to a smaller room where the greatwyrm keeps relics that are too precious for the main hoard or that don’t match the hoard’s overall aesthetic.

Lair Actions

On initiative count 20 (losing initiative ties), the greatwyrm takes a lair action to cause one of the following effects; the greatwyrm can’t use the same effect two rounds in a row:

Blinding Cloud. A cloud of sand swirls about in a 20-foot-radius sphere centered on a point the greatwyrm can see within 120 feet of it. The cloud spreads around corners. Each creature in the cloud must succeed on a DC 15 Constitution saving throw or be blinded for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Collapse Ceiling. Part of the ceiling collapses above one creature that the greatwyrm can see within 120 feet of it. The creature must succeed on a DC 15 Dexterity saving throw or take 14 (4d6) bludgeoning damage and be knocked prone and buried. The buried target is restrained and unable to breathe or stand up. A creature can take an action to make a DC 10 Strength check, ending the buried state on a success.

Lightning Strikes. Lightning arcs, forming a 5-foot-wide line between two of the lair’s solid surfaces that the greatwyrm can see. They must be within 120 feet of the greatwyrm and 120 feet of each other. Each creature in that line must succeed on a DC 15 Dexterity saving throw or take 9 (2d8) lightning damage.

Misleading Mirage. Until initiative count 20 on the next round, at each intersection or branching passage in the lair, a creature other than the greatwyrm has a 50 percent chance of going in a different direction from the direction it intends.

Sudden Sinkhole. The greatwyrm chooses a point on the ground that it can see within 120 feet of it. A 5-foot-radius, 20-foot-deep pit forms centered on that point. A creature on the ground above where the pit formed must make a DC 15 Dexterity saving throw. On a failed save, a creature falls to the bottom of the pit, taking 7 (2d6) bludgeoning damage and landing prone. On a successful save, a creature moves to the nearest unoccupied space instead of falling in the pit.

Regional Effects

The region containing an ancient blue greatwyrm's lair is warped by the greatwyrm's magic, which creates one or more of the following effects:

Blue Luster. Creatures that spend a year within 1 mile of the ancient blue greatwyrm's lair find blue objects fascinating and feel compelled to acquire them at every opportunity.

Mirage Terrain. The area immediately surrounding the lair appears to be a lush oasis. A creature carefully examining the illusion can attempt a DC 15 Intelligence (Investigation) check to disbelieve it. A creature who disbelieves the illusion sees it as a vague image superimposed on the underlying terrain.

Raging Storms. Thunderstorms rage within 6 miles of the lair.

Sandstorm. A sandstorm filled with dust devils blows constantly within 1 mile of the ancient blue greatwyrm's lair.

Sinkholes Abound. Hidden sinkholes form in and around the ancient blue greatwyrm's lair. A sinkhole can be spotted from a safe distance with a successful DC 20 Wisdom (Perception) check. Otherwise, the first creature to step on the thin crust covering the sinkhole must succeed on a DC 15 Dexterity saving throw or fall 1d6 × 10 feet into the sinkhole.

If the greatwyrm dies, the dust devils disappear immediately, and the other effects abate within 1d10 days. Any sinkholes remain where they are.