Storm Dragon

Gargantuan dragon, chaotic evil

Armor Class

20 (natural armor)

Hit Points

310 (20d20 + 100)

Speed

40 ft., fly 80 ft., swim 40 ft.

Saves

Str +12, Con +12, Wis +12

Skills

Insight +12, Perception +12

Senses

darkvision 90 ft.

Languages

Draconic, Primordial

Challenge

23

Innate Spellcasting

The storm dragon's innate spellcasting ability is Wisdom (spell save DC 22). It can innately cast the following spells, requiring no material components • 2/Day: control water, dispel magic, fog cloud, gust of wind • 1/Day: chain lightning, conjure elemental (water), control weather, plane shift, tsunami

Legendary Resistance (3/Day)

If the storm dragon fails a saving throw, it can choose to succeed instead.

Siege Monster

The storm dragon does double damage to objects and structures.

Storm Vision

The storm dragon can see normally through light or heavy obscurement caused by high winds, heavy rain, fog, clouds, or mist.

Actions

Multiattack

The storm dragon makes three attacks: one with its bite and two with its claws.

Bite

Melee Weapon Attack: +16 to hit, reach 15 ft., one target. Hit: 16 (2d10 + 5) piercing damage.

Claw

Melee Weapon Attack: +16 to hit, reach 10 ft., one target. Hit: 12 (2d6 + 5) slashing damage.

Tail

Melee Weapon Attack: +16 to hit, reach 20 ft., one target. Hit: 14 (2d8 + 5) bludgeoning damage.

Breath Weapon (Recharge 5-6).

The sea dragon shoots out a powerful burst of water in a 120-ft. line that is 10 feet wide. Each creature in that line must make a successful DC 22 Dexterity saving throw or take 88 (16d10) force damage and be knocked prone, 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 storm dragon beats its wings. Each creature within 10 feet of the storm dragon must succeed on a DC 22 Dexterity saving throw or take 12 (2d6 + 5) bludgeoning damage and be knocked prone. The sea dragon can then fly up to half its flying speed.