Gargantuan Dragon, typically Neutral
Armor Class 22 (natural armor)
Hit Points 409 (21d20 + 189)
Speed 30 ft., swim 60 ft.
STR
28 (+9)
DEX
12 (+1)
CON
29 (+9)
INT
14 (+2)
WIS
19 (+4)
CHA
15 (+2)
Saving Throws Dex +8, Con +16, Wis +11
Skills Perception +11
Damage Immunities cold, fire
Condition Immunities charmed, frightened, poisoned
Senses truesight 120 ft., passive Perception 21
Languages Aquan, Draconic
Challenge 24 (62000 XP)
Proficiency Bonus +7
Amphibious.
Blessing of the Sea (Recharges after a Short or Long Rest).
Legendary Resistance (3/Day).
Unusual Nature.
Actions
Multiattack.
Bite.
Claw.
Tail.
Steam Breath (Recharge 5-6).
Legendary actions
Attack.
Move.
Boiling Aura (Costs 3 Actions).
Mythic actions
Bite.
Armor of Storms (Costs 2 Actions).