Vaelthun, Voice of the Glacial Tempest

Amphibious. Vaelthun can breathe air and water.

Titanic power (Recharges after a short or long rest). If Vaelthun would be reduced to 0 hitpoints, its current hit point total would instead reset to 600 hit points, it's shell would regrow with ice and regain 150 hit points up to it's maximum hit points. In addition it's breathweapon recharges and it gains access to his hail breath feature of it's breath weapon and any features marked with "(Titanic)", and also gains access to its mythic actions section for 1 hour.

Hailing tempest (Titanic). the area within 150 feet of Vaelthun is under the effect of ice storm. creatures make their saving throw when they enter the area or start their turn there.

Charged ice (Titanic). When Vaelthun deals damage with the  ice storm spell , it deals an additional 26 (4d12) lightning damage.

Geographic shell. Vaelthun takes no damage from attacks that deal under 20 damage.

Unmovable. The creature can not be moved against it will.

Immutable Form. The golem is immune to any spell or effect that would alter its form.

Legendary Resistance (3/Day). If the dragon turtle fails a saving throw, it can choose to succeed instead.

Gigantic body. Vaelthun's body is gigantic. it has several areas on its body which can be targeted and broken. these parts have their own health pool, but Vaelthun takes half the damage a part takes when they take damage.

• Shell. 21 AC. 200 hp. when this is broken, it deactivates it's geographic shell feature.
• eyes 150 hp. this part automatically takes damage when Vaelthun takes radiant damage. when this is broken, it is blinded from its normal sight and can only use its truesight to see.
• Legs. 21 AC. 130 hp. when this is broken it can no longer use its tidal wave action or its splash legendary action.
• Lungs. 150 hp. This part automatically takes damage when Vaelthun takes necrotic damage. when this is broken, it can no longer use its steam breath or steam bubble breath weapon.

Diving body. When Vaelthun dives under water, any creature that is holding on to it with a strenght score of 19 or lower lets go and doesn't go with it.

Lumbering body. when a ship makes a Saving throw against Vaelthun the DC for that roll is 17 instead.

Multiattack. Vaelthun can make a bite attack, a lightning strike attack, a hail storm and a tidal wave. it can switch its bite attack for any of the other attacks that quallify for multiattack. When it's Titanic Power trait has been activated in the last hour, it can use three of these action to use it's hailbolt instead.

Bite. Melee Weapon Attack: +9 to hit, reach 30 ft., 1 target. Hit: 30 (3d12 + 10) piercing damage and 14(4d12) lightning damage.

Lightning strike. Ranged Weapon Attack: +9 to hit, range 500 ft., 1 target. Hit: 14 (4d12) Lightning damage. if this is cast in an area that has been affected by the ice storm cast by vaethun this turn, then it deals additional 7(1d12) lightning damage to the effected area. up to a circle with a 10 foot diameter where it struck.

Hail storm. Vaelthun can cast ice storm. if Vaelthun uses this action while it's Hailing tempest feature is active, it increases the level of the spell for each time its used until the start of it's next turn. Creatures on a ship have resistance to the damage of the spell.

Tidal wave. Vaelthun cam cast tidal wave.

Breath weapon (Recharge 5-6). Vaelthun can use one of the following breath attacks. crew on their ship only take the damage from it's breath weapon if they are within 90 feet of vaelthun.

• Hail breath. Vaelthun unleashes a cone of hail and lightning in a 300-foot cone, Each creature and struckture must succeed on a DC 22 Dexterity saving throw, Taking 41(9d8) bludgeoning damage, 27(6d8) cold damage and 46(7d12) lightning damage. this area is difficult terain 3 rounds. if ships choose to sail through it at normal speed then they take 7(2d6) bludgeoning damage for each space moved. this damage igonores the damage treashold for ships.
• Steam breath. Vaelthun exhales steam in a 300-foot cone. Each creature or Structure within that area must succeed on a  DC 22 Constitution saving throw, taking 90(20d8) fire damage on a failed save, or half as much on a successful one. Being underwater doesn't grant resistance agaisnt this damage.
• Steam buble. Vaelthun releases a buble filled with steam to a location within 180 feet of him, a Structure or creature must succeed on a DC 22 Constitution saving throw or take67(15d8) force damgage and be launched 60 feet in a direction of the dragon turtles choice on a failure, or half as much damage on a successfull one. Structures are resistant to this damage. Being underwater doesn't grant resistance agaisnt this damage.

HailBolt(1/day) (Titanic). Vaelthun creates a 40-foot-radius hail stone that is surging with lightning in a location within 1 mile that falls down at the start of Vaelthun's next turn.. when it hits the surface, any creature or structure under the stone must succeed on a DC 22 Dexterity saving throw taking 70(20d6) Bludgeoning and 70(20d6) cold damage and becoming prone and restrained until freed (The stone has an AC of 15 and 50 hitpoints). it then can then use its lightning strike action to strike it in a gigantic bolt, destroying the stone and forcing all structures and creatures within 50 feet of the stonne to make a DC 22 Dexterity saving throw, Taking 36(5d12) lightning damage. creatures Restrained by the ice automatically fail this saving throw.

Vaelthun can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. Vaelthun  regains spent legendary actions at the start of its turn.

Storm well. Vaelthun can make either a bite attack or a lightning strike attack

Splash. Vaelthun casts the tidal wave.

Dive (Costs 2 Actions). Vealthun submerges under water, all structures and creatures that are drifting in water within 100 feet of it must succeed on a DC 22 strenght saving throw or be pulled to his orginal location. it resurfaces at the start of its turn within 150 feet of his location.

If Vaelthun's Titanic power trait has been activated int he last hour, it can use the options below as if they were legendary actions

Hail blast. Vaelthun fires a large hailstone that is charged with lightning to a point within 400 feet of him that he can see. The creature or structure must succeed on a DC 22 Dexterity saving throw, taking 27(6d8) cold damage and 26(4d12) lightning damage.

Hail strike (Costs 2 Actions). Vaelthun creates 7 chunks of ice that are charged with lightning. Make a Ranged attack: +9 for each chunk, on a hit the target takes 7(2d6) cold damage and 7 (1d12) lightning damage