A blue-gold dragon in its true form is easily recognized by its large, twin horns that are smooth, twin neck frills, and the whiskers around its mouth that look like the barbels of a catfish. It has one large singler sharp, horn on its snout

Blue-Gold dragons make their lairs in out-of-the-way places, where they can do as they please without arousing suspicion or fear. Most dwell near idyllic lakes and rivers, mist-shrouded islands, cave complexes hidden behind sparkling waterfalls, or ancient ruins, using their lightning breath and their burrowing ability to carve out crystallized caverns and tunnels beneath the sands.

A blue-gold dragon will collapse the caverns that make up its lair if that lair is invaded. The dragon 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.

Lair Actions

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

• Part of the ceiling collapses above one creature that the dragon can see within 120 feet of it. The creature must succeed on a DC 15 Dexterity saving throw or take 10 (3d6) 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.
• A cloud of sand swirls about in a 20-foot-radius sphere centered on a point the dragon 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.
• Lightning arcs, forming a 5-foot-wide line between two of the lair’s solid surfaces that the dragon can see. They must be within 120 feet of the dragon and 120 feet of each other. Each creature in that line must succeed on a DC 15 Dexterity saving throw or take 10 (3d6) lightning damage.
• One creature the dragon can see within 120 feet of it must succeed on a DC 15 Charisma saving throw or be banished to a dream plane, a different plane of existence the dragon has imagined into being. To escape, the creature must use its action to make a Charisma check contested by the dragon’s. If the creature wins, it escapes the dream plane. Otherwise, the effect ends on initiative count 20 on the next round. When the effect ends, the creature reappears in the space it left or in the nearest unoccupied space if that one is occupied.
• The dragon glimpses the future, so it has advantage on attack rolls, ability checks, and saving throws until initiative count 20 on the next round.
• Jagged ice shards fall from the ceiling, striking up to three creatures underneath that the dragon can see within 120 feet of it. The dragon makes one ranged attack roll (+7 to hit) against each target. On a hit, the target takes 10 (3d6) piercing damage.
• The dragon creates an opaque wall of ice on a solid surface it can see within 120 feet of it. The wall can be up to 30 feet long, 30 feet high, and 1 foot thick. When the wall appears, each creature within its area is pushed 5 feet out of the wall’s space, appearing on whichever side of the wall it wants. Each 10-foot section of the wall has AC 5, 30 hit points, vulnerability to fire damage, and immunity to acid, cold, necrotic, poison, and psychic damage. The wall disappears when the dragon uses this lair action again or when the dragon dies.
• Freezing fog fills a 20-foot-radius sphere centered on a point the dragon can see within 120 feet of it. The fog spreads around corners, and its area is heavily obscured. Each creature in the fog when it appears must make a DC 10 Constitution saving throw, taking 10 (3d6) cold damage on a failed save, or half as much damage on a successful one. A creature that ends its turn in the fog takes 10 (3d6) cold damage. A wind of at least 20 miles per hour disperses the fog. The fog otherwise lasts until the dragon uses this lair action again or until the dragon dies.

Regional Effects

The region containing a legendary blue-gold dragon’s lair is warped by the dragon’s magic, which creates one or more of the following effects:

• Thunderstorms rage within 6 miles of the lair.
• Dust devils scour the land within 6 miles of the lair. A dust devil has the statistics of an air elemental, but it can’t fly, has a speed of 50 feet, and has an Intelligence and Charisma of 1 (−5).
• Hidden sinkholes form in and around the dragon’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.
• Banks of beautiful, opalescent mist manifest within 6 miles of the dragon’s lair. The mist doesn’t obscure anything. It assumes haunting forms when evil creatures are near the dragon or other non-evil creatures in the mist, warning such creatures of the danger.
• Gems and pearls within 1 mile of the dragon’s lair sparkle and gleam, shedding dim light in a 5-foot radius.
• Whenever a creature that can understand a language sleeps or enters a state of trance or reverie within 6 miles of the dragon’s lair, the dragon can establish telepathic contact with that creature and converse with it in its dreams. The creature remembers its conversation with the dragon upon waking.
• Freezing precipitation falls within 6 miles of the dragon’s lair, sometimes forming blizzard conditions when the dragon is at rest.
• Icy walls block off areas in the dragon’s lair. Each wall is 6 inches thick, and a 10-foot section has AC 5, 15 hit points, vulnerability to fire damage, and immunity to acid, cold, necrotic, poison, and psychic damage.
  If the dragon wishes to move through a wall, it can do so without slowing down. The portion of the wall the dragon moves through is destroyed, however.
• Chilly fog lightly obscures the land within 6 miles of the dragon’s lair.

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