Sea Dragon, Adult

Family: Dragon - Sea

Huge dragon, chaotic good

Armor Class 19 (natural armor)
Hit Points 279 (18d12+162)
Speed 40 ft., fly 100 ft., swim 90 ft.

28 (+9) 8 (+0) 29 (+9) 22 (+6) 23 (+6) 22 (+6)

Saving Throws Str +15, Con +15
Damage Immunities lightning
Skills Perception +15, Persuasion +15
Senses blindsight 60 ft., darkvision 60 ft., passive Perception 25
Languages Aquan, Auran, Celestial, Common, Draconic, Elvish, Sylvan
Challenge 20 (25,000 XP)



  • Multiattack. The imperial sea dragon can use its Frightful Presence. It then makes three attacks: one with its bite and two with its claws.
  • Bite. Melee Weapon Attack: +15 to hit, reach 5 ft., one target. Hit: 35 (4d12 + 9) piercing damage.
  • Claw. Melee Weapon Attack: +15 to hit, reach 5 ft., one target. Hit: 27 (4d8 + 9) slashing damage.
  • Tail. Melee Weapon Attack: +15 to hit, reach 5 ft., one target. Hit: 27 (4d8 + 9) bludgeoning damage.
  • Frightful Presence. Each creature of the imperial sea dragon’s choice that is within 120 feet of the imperial sea dragon and aware of it must succeed on a DC 19 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 imperial sea dragon’s Frightful Presence for the next 24 hours.
  • Wave Breath (Recharge 5-6). The imperial sea dragon exhales a torrent of water in a 60-foot cone. Each creature in that cone must make a DC 19 Dexterity saving throw, taking 33 (6d10) bludgeoning damage on a failed save, or half as much damage on a successful one. Creatures failing their saving throw must make a DC 19 Strength saving throw or be forced prone.


The imperial sea dragon 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. The imperial sea dragon regains spent legendary actions at the start of its turn.

  • Detect. The imperial sea dragon makes a Wisdom (Perception) check.
  • Tail Attack. The imperial sea dragon makes a tail attack.


On initiative count 20 (losing initiative ties), the imperial sea dragon takes a lair action to cause one of the following effects; The imperial sea dragon can’t use the same effect two rounds in a row:

  • A imperial sea dragon can summon one creature that lives in the sea that is CR 2 or less to a space within 60 feet of it. This creature is loyal to the imperial sea dragon and will do anything to defend it.
  • The imperial sea dragon can cause the currents in its lair to push up to 4 creatures 60 feet away from the spaces they started in. These creatures must succeed a DC 19 Strength saving throw to avoid being forcefully moved like this.
  • The imperial sea dragon can cause a 10 foot radius area of water to become electrified. Creatures in the area must succeed a DC 19 Dexterity saving throw or take 7 (2d6) lightning damage.


The region containing the imperial sea dragon’s lair is shaped by the its immense power, which creates one or more of the following effects:

  • Seas within 5 miles of the imperial sea dragon’s lair become strangely serene and without many waves unless the dragon wishes it.
  • Poisonous, stagnant, or otherwise foul water within 1 mile of the imperial sea dragon’s lair becomes fresh and safe to drink.
  • Sea creatures within 1 mile of the imperial sea dragon‘s lair are strangely non-aggressive towards outsiders such as humanoids.


Infused with the power of waves and storms, sea dragons are draconic protectors of bodies of water, with young sea dragons concerning themselves more with small rivers and lakes and elder sea dragons guarding oceans and their creatures.

Possessing tempestuous natures, sea dragons wander widely, sometimes claiming thousands of miles of ocean and coastlines as their protectorates. The long, undulating bodies of these serpentine dragons roll and bend with scales the color of the ocean’s waves.

Dragons are an integral part of the mythology of Asia, though they are quite different from the winged dragons known in the Western mythology. Some are benevolent and others sinister, but while their appearance is different from Western dragons they are equally capable of the savage rapacity and legendary greed of their chromatic cousins and the stern and aloof devotion to goodness of their metallic kin. Like most monsters, imperial dragons have an assigned typical alignment, but they are highly individualistic and much more likely to have an alignment that varies from the typical than would be true for metallic or chromatic dragons.

Imperial dragons, sometimes termed dragons of the celestial host, in the “dragon empires” are serpentine agents of cosmic balance, though some of them are not above sowing chaos and discord for their own gain. Imperial dragons differ in appearance from the more commonly known chromatic and metallic dragons, possessing a long serpentine body. Most lack wings but can fly gracefully through supernatural means.

All imperial dragons have large antlers, some sweeping back in delicate curves and others thrust forward to gore their foes.

Like all dragons, imperial dragons can breathe potent torrents of elemental force, and many can cast spells and perform other supernatural feats. Additionally, all can magically transform themselves into a humanoid shape.

Imperial Entanglements. Imperial dragons are defenders of ancient lands and protectors of cosmic balance. They take a much more active role in humanoid societies than their metallic or chromatic kin, to such a degree that the kingdoms of in lands they are known sometimes refer to themselves as “dragon empires.” They are active in times of social upheaval, and may be sought out for their wisdom or aid. Imperial dragons are seen by humanoids as either benevolent guardians or vile threats depending on their type. Some imperial families trace their bloodlines to the semi-divine dragon-emperors of old or still rely on the counsel of living dragons or, in rare cases, ask a dragon to rule as their wise sovereign.

Mandate of Heaven. More so than any other dragons, imperial dragons are closely tied to the religious beliefs of their native lands. Imperial dragons are often associated with divinity, whether as guardians or emissaries of a god, as the representation of a god, or as a deity themselves. It is said that imperial dragons inhabited their lands in an Age of Dragons, long before other races arose there, and were charged by the gods to safeguard the land in anticipation of humanity’s arrival. Some of the gods themselves may in fact be incredibly powerful dragons transcended into immortality, and each of the five species of imperial dragon is represented as a constellation.

Adult Dragons. The imperial dragons presented in this book are all adults. As agents of the highest deities, young dragons sometimes wander in mortal lands before they ascend, though many are kept safe in the realms of the divine until they reach maturity and complete their training. Older dragons may likewise “graduate” from their status and join the celestial bureaucracy, while others roam freely to live as they wish. If you wish to extend the lifespans of imperial dragons into youth or old age like other true dragons, you can adjust their abilities up or down in a manner similar to other dragons with equivalent Challenge levels.

Section 15: Copyright Notice

Asian Monsters (5E) © 2021, Legendary Games; Authors Miguel Colon, Jason Nelson, Andrew Ha, Aurélien Lainé, Dan Dillon, Ismael Alvarez, James-Levi Cooke, Robert J. Grady, Jeff Ibach, Matt Kimmel, and Thurston Hillman

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