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Adult Sea Dragon

Adult Sea Dragon 5e reference with CR 18, type, stat block details, token resources, terrain tools, fear hooks, and monster hunt generation.

CR 18DragonStat Block + PDFHunt Ready
Original 5e-Compatible Stat BlockDownload PDF

Overview

An adult sea dragon is a huge marine dragon of depth and storm, a third-party inclusion under tolerance level 1.

Quick 5e Answer

Adult Sea Dragon CR, type, stat block, and table tools

Adult Sea Dragon is a CR 18 dragon for D&D 5e. This page includes AC 20, HP 287 (23d12 + 138), a ready stat block, a downloadable PDF, and connected encounter tools.

CR18
TypeDragon
Stat BlockOriginal 5e-Compatible Stat Block
PDF SheetAvailable
AC20
HP287 (23d12 + 138)

Original 5e-Compatible Stat Block

Adult Sea Dragon

Huge, Dragon, Neutral

Original 5e5e-compatiblemonster-almanac-original-v1PDF Ready
Download PDF

This is an original Monster Almanac 5e-compatible stat block, not an official SRD stat block.

Armor Class20
Hit Points287 (23d12 + 138)
Challenge18 β€’ 20,000 XP
Proficiency+6
Speed
Fly 80 ft., Swim 80 ft., Walk 30 ft.
Initiative
+3
Saving Throws
Cha +11, Con +12, Dex +9, Wis +10
Skills
Stealth +9, Perception +16
Damage Resistances
Cold, Lightning
Senses
Blindsight 60 ft., Darkvision 120 ft.; Passive Perception 26
Passive Perception
26
Languages
Aquan, Common, Draconic
STR28+9
DEX16+3
CON22+6
INT18+4
WIS18+4
CHA20+5

Traits

Lord of Tides

The dragon ignores difficult terrain caused by water, surf, kelp, mud, and ship debris.

Crushing Depths

Creatures Grappled by the dragon cannot regain Hit Points and have Disadvantage on Strength saving throws.

Actions

Multiattack

The dragon makes three attacks: Bite and two Claws.

Bite

Melee Attack Roll: +15, reach 15 ft. Hit: 35 (4d12 + 9) Piercing damage plus 22 (5d8) Cold damage.

Claw

Melee Attack Roll: +15, reach 10 ft. Hit: 16 (2d6 + 9) Slashing damage.

Drowning Breath (Recharge 5-6)

Strength Saving Throw: creatures in a 60-foot Cone. Failure: 108 (24d8) Bludgeoning and Cold damage, split evenly, and the target is pushed 30 feet. Success: Half damage.

Reactions

Tidal Reposition

When missed by an attack, the dragon swims or flies up to 20 feet without provoking Opportunity Attacks.

Legal Attribution

Original Monster Almanac compatible game statistics. This entry is designed for 5e-style tabletop play and does not reproduce closed-book stat block text.

Generated by Monster Almanac. This is original compatible game content, not an official SRD stat block.

License: Monster Almanac Original Compatible Content

Generate Terrain

Coastal

Base + optional customizer

Custom
Morning β€’ Clear β€’ Sandy Beach β€’ Low Tide β€’ Shipwreck
BaseOpen

Wilderness

Base + optional customizer

Custom
Morning β€’ Clear β€’ Open Clearings β€’ Thorn Brambles β€’ Hunter Camp
BaseOpen

Note: These resource links work best when you are logged in to ChatGPT in your browser.

Adult Sea Dragon Token, Portrait, Chatbot, Terrain, Fear Hooks, Hunt Generator, and D&D 5e Resources

Adult Sea Dragon 5e reference: CR 18 dragon, AC 20, HP 287 (23d12 + 138), PDF sheet, token, portrait, terrain, fear hooks, and hunt tools for Ocean,… This page is part of the complete Monster Almanac stat block library. It includes a original 5e-compatible stat block with a downloadable PDF sheet, plus connected prep tools. Use this Monster Almanac page to move from search result to table prep: read the quick 5e reference, open the stat block, download the PDF when available, generate a token or portrait prompt, build matching terrain, create a monster-bound fear hook, and turn Adult Sea Dragon into a focused hunt.

Using Adult Sea Dragon in play

Adult Sea Dragon can be used in Ocean, Coastal, Wilderness when you want a CR 18 dragon that helps shape combat pressure, exploration tension, or narrative danger.

Adult Sea Dragon works well as a supporting threat, recurring danger, or encounter-building piece inside a larger scene.

The attached original 5e-compatible stat block gives you a table-ready rules reference, and the PDF button keeps the sheet easy to print or save before the session.

This makes Adult Sea Dragon useful not only as a monster reference, but also as a scene-shaping piece for travel danger, dungeon pressure, wilderness discovery, or a stronger narrative threat.

Why this monster is useful

  • Fits naturally into Ocean, Coastal, Wilderness.
  • Works as a CR 18 option for encounter building and pacing.
  • Connects directly with a stat block, downloadable PDF, portrait, token, chatbot, terrain, fear hook, and hunt resources.
  • Helps game masters move from reference to actual tabletop use more quickly.

Quick ideas for scene building

  • Use Adult Sea Dragon as a wandering threat tied to the local environment.
  • Pair the monster with terrain from the environments shown above.
  • Add an NPC witness, hunter, scholar, survivor, or fearful character to frame the danger.
  • Open the chatbot resource to give the creature more roleplay or lore flavor.
  • Use the hunt generator to turn this monster into a focused adventure hook.

Adult Sea Dragon 5e quick FAQ

What CR is Adult Sea Dragon in D&D 5e?

Adult Sea Dragon is listed in Monster Almanac as a CR 18 dragon.

What type of monster is Adult Sea Dragon?

Adult Sea Dragon is listed as a dragon.

Does Adult Sea Dragon have a 5e stat block?

Yes. This page includes a original 5e-compatible stat block and a downloadable PDF sheet.

Can I generate a token or hunt for Adult Sea Dragon?

Yes. This page links to Adult Sea Dragon token, portrait, chatbot, terrain, fear hook, and monster hunt tools for fast D&D prep.