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Portrait of the Ancient Marsh Dragon
Creature · Built-in

Ancient Marsh Dragon

Gargantuan Dragon, neutral

  • Boss difficulty
  • CR 16
  • Melee
  • Tank
  • Flying
  • Boss

An old and patient tyrant, slick with bog water, whose name is a curse in three kingdoms.

Statistics

Armor Class
20 (scales)
Hit Points
350 (20d20 + 140)
Speed
Walk 40 ft, Fly 80 ft, Swim 40 ft
Challenge
CR 16 · 15000 XP
Size
Gargantuan — Takes a 4-by-4 block of map cells.
Saving throws
DEX +5, CON +12, WIS +7
Skills
Perception +7, Stealth +5
Senses
Blindsight 10 ft, Darkvision 60 ft
Languages
Common, Draconic
STR26+8
DEX10+0
CON24+7
INT16+3
WIS15+2
CHA19+4

Attacks

Multiattack

Bite, Claw × 2

Bite Melee

+13 to hit · Reach 15 ft (3 map cells)

Damage: 2d12 + 8 piercing

Claw Melee

+13 to hit · Reach 10 ft (2 map cells)

Damage: 2d8 + 8 slashing

Abilities

Marsh Breath Recharge 5–6

Exhales a line of acid.

Area
60 ft
Saving throw
Dexterity DC 20
On a failed save
Full damage.
On a successful save
Half damage.
Damage
15d6 acid

Old Cunning At will

GM guidance: has seen every trick before; it fights from the ground it chose and leaves by the exit it prepared.

Wing Gust At will

GM guidance: beats its wings to scatter anyone close, or lifts into the air out of reach.

Defenses

Immunities
Acid

Environment & tags

Environments
Swamp
Groups
Dragons, Aquatic, Swamp
Tags
dragon, marsh, hoard, boss