Easily the most friendly and talkative of the gem dragons, crystal dragons are voraciously curious and usually quite affable to travelers and strangers (unless of course they are overtly hostile). A crystal dragons has white skin and a sleek profile; many individuals mistake a crystal dragon for a white dragon, though crystal dragons lack the crest. Instead, it has a trail of shard-like translucent spines down its back and tail. Its tail splits into two about halfway down its length. When it is a wyrmling, a crystal dragon's scales are glossy white. As it ages, its scales become translucent and refract light. Moonlight and starlight gleams in its scales, and direct sunlight lends it dazzling brilliance; the older the dragon, the more brilliant it becomes.

Insatiable Curiosity. Crystal dragons are notoriously curious about anything and everything. They often stop travellers on their way, just so they can get to know them and ask them questions about where they are from and where they are going to. The phrase "curiosity killed the crystal dragon" is in many cases more true than "curiosity killed the cat," as some (especially younger) crystal dragons will intentionally enter dangerous situations just to learn about them. Of course, the dragon (nearly) always learns its lesson, so adult dragons are a bit wiser when it comes to such things. As a result of this curiosity, most crystal dragons accumulate impressive libraries of knowledge over time and spend centuries mulling over history, magic, or any number of other subjects that a particular dragon might find interest in. They also give quite freely of their knowledge to those who are curious enough to ask, because of course curiosity must be rewarded.

Ice Affinity. Crystal dragons prefer colder environments, and have developed a natural immunity to cold. Though they aren't built to burrow in ice and snow, they do love the feel of it between their claws and the camouflage it offers when hunting. Many crystal dragons carve sculptures from ice and snow as a hobby, and their lairs become littered with past and present projects.

White Dragon Dopplegangers. Because of their appearance and preferred habitat, crystal dragons are often mistaken for white dragons. They resent this confusion, as they take pride in their intelligence and take offense to the notion that they would stoop to such primal levels. However, a crystal dragon doesn't usually have time to explain itself before the mistaken creature attacks it. And then the creature becomes dinner anyway. Though they lack the hunting instincts of white dragons, crystal dragons are terrifying combatants. They rarely instigate combat on their own, but they do not hesitate to defend themselves and their lair if attacked. Because they share a similar territory to white dragons, crystal dragons and white dragons come into conflict. The crystal dragons aren't fond of their bestial neighbors, and have been known to steal white dragon eggs so that they can raise the white hatchlings to be friendlier than they would otherwise be. Such white dragons are incredibly rare. Crystal dragons bear great animosity toward frost giants, because of their routine of hunting down dragon lairs and wyrmlings.

Most crystal dragons live on the Elemental Plane of Air, though some occasionally choose to live on the Frostfell. When on the Material Plane, they try to find places that mimic either of those two places, usually ending up on high, icy mountain peaks where they can create ice sculptures and watch the stars. A crystal dragon spends more time outside of its lair than inside. To a crystal dragon, the sky is symbolic of freedom, so it spends as much time on the wing as possible, patrolling its territory or exploring new places and discovering new things. Because mountain peaks are so inaccessible to passersby, the dragon may claim a temporary lair near a well-travelled road, or frequent the road or nearby settlements to learn of current events and to temporarily satiate its curiosity.

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:

• The dragon suddenly gleams with a flash of brilliant scintillating light. Each creature within 30 feet of the dragon that can see it must succeed on a DC 15 Dexterity saving throw to shield its eyes, or be blinded until the end of its next turn.

• The dragon can choose a point it can see on the ground within 60 feet of it. A large crystal falls from the ceiling and shatters on that point. Each creature within 10 feet of that point must succeed on a DC 15 Dexterity saving throw or take 10 (3d6) bludgeoning damage from the crystal shards.

• The dragon stirs up strong winds within its lair. The dragon chooses the direction of the wind. Until initiative count 20 of the following round, ranged attacks made in the winds are made with disadvantage, and any creature moving against the wind must spend 1 extra foot of movement for each foot moved.

Regional Effects

The region containing a legendary crystal dragon's lair is warped by the dragon's magic, which creates one or more of the following effects:

• The walls of the dragon's lair become translucent and reflective, like polished crystal. In addition, the walls glow faintly, giving off dim light. The dragon can extinguish or restore this light at will, no action required.
• Crystal formations grow spontaneously within 6 miles of the lair.
• Crystal within 1 mile of the lair glows slightly and feels warm to the touch.

If the dragon dies, these effects end immediately, but any crystal formations remain as they are.