Cryovain (upscaled)

White Dragons are instinctive and cunning predators. They are confident in their ability to slay most foes they face, which shows in their vain and confident behaviour. They try to kill their prey with fly-by bite, claw and breath attacks.

Being a Young Ice Dragon, Cryovain behaves much in the same way. Although when he notices that his opponents start gaining an edge during a fight and he starts taking some serious damage he will start using his lair actions, if the fight is taking place in his lair. Otherwise he will attempt to retreat to his lair in order to recover.

If he is on the brink of losing the fight he will go into a blind rage and will start thrashing about wildly trying to deal as much damage as he can.

If the players manage injure Cryovain's wings, his flying speed will be reduced by 10ft per moderate injury. If they manage to significantly injure at least one wing Cryovain will lose his ability to fly and if he is airborne, he will crash onto the platform.

A White Dragon’s Lair

White dragons lair in icy caves and deep subterranean chambers far from the sun. They favor high mountain vales accessible only by flying, caverns in cliff faces, and labyrinthine ice caves in glaciers. White dragons love vertical heights in their caverns, flying up to the ceiling to latch on like bats or slithering down icy crevasses.

A white dragon rests on high ice shelves and cliffs in its lair, the floor around it a treacherous morass of broken ice and stone, hidden pits, and slippery slopes. As foes struggle to move toward it, the dragon flies from perch to perch and destroys them with its freezing breath.

Lair Actions - after Cryovain drops below 50% HP

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:

• Freezing fog fills a 15-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 (2d6) 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 7 (2d6) 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.
• 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.

Regional Effects

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

• Chilly fog lightly obscures the land within 6 miles of the dragon’s lair.
• Freezing precipitation falls within 6 miles of the dragon’s lair, sometimes forming blizzard conditions when the dragon is at rest.

If the dragon dies, the fog and precipitation fade within 1 day. The ice walls melt over the course of 1d10 days.