Armor Class20
Hit Points333 (18d20+144)
Speed40 ft., burrow 40 ft., fly 80 ft., swim 40 ft.
ChallengeCR 20 (25,000 XP)
STR
26
(+8)
DEX
10
(+0)
CON
26
(+8)
INT
10
(+0)
WIS
13
(+1)
CHA
14
(+2)
Saving ThrowsDEX +6, CON +14, WIS +7, CHA +8
SkillsPerception +13, Stealth +6
Immunitiescold
Sensesblindsight 60 ft., darkvision 120 ft., passive Perception 23
LanguagesCommon, Draconic
Special Abilities
Ice Walk. The dragon can move across and climb icy surfaces without needing to make an ability check. Additionally, difficult terrain composed of ice or snow doesn't cost it extra moment.
Legendary Resistance. If the dragon fails a saving throw, it can choose to succeed instead.
Actions
Multiattack. The dragon can use its Frightful Presence. It then makes three attacks: one with its bite and two with its claws.
Bite. Melee Weapon Attack: +14 to hit, reach 15 ft., one target. Hit: 19 (2d10 + 8) piercing damage plus 9 (2d8) cold damage.
Claw. Melee Weapon Attack: +14 to hit, reach 10 ft., one target. Hit: 15 (2d6 + 8) slashing damage.
Tail. Melee Weapon Attack: +14 to hit, reach 20 ft., one target. Hit: 17 (2d8 + 8) bludgeoning damage.
Frightful Presence. Each creature of the dragon's choice that is within 120 feet of the dragon and aware of it must succeed on a DC 16 Wisdom saving throw or become frightened 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. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the dragon's Frightful Presence for the next 24 hours .
Cold Breath. The dragon exhales an icy blast in a 90-foot cone. Each creature in that area must make a DC 22 Constitution saving throw, taking 72 (l6d8) cold damage on a failed save, or half as much damage on a successful one.
Legendary Actions
Detect. The dragon makes a Wisdom (Perception) check.
Tail Attack. The dragon makes a tail attack.
Wing Attack (Costs 2 Actions). The dragon beats its wings. Each creature within 15 ft. of the dragon must succeed on a DC 22 Dexterity saving throw or take 15 (2d6 + 8) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed.