Ancient Black Dragon

Gargantuan Dragon (Chromatic), Chaotic Evil
Initiative +16 (26)
AC 22
HP 367 (21d20 + 147)
Speed 40 ft., Fly 80 ft., Swim 40 ft.
MOD
SAVE
MOD
SAVE
MOD
SAVE

Str
27
+8
+8
Dex
14
+2
+9
Con
25
7
+7

Int
16
+3
+3
Wis
15
+2
+9
Cha
22
+6
+6

Skills Perception +16, Stealth +9
Immunities Acid
Senses Blindsight 60 ft., Darkvision 120 ft., Passive Perception 26
Languages Common, Draconic
CR 21 (XP 33 000, or 41 000 in lair; PB +7)
Traits

Amphibious. The dragon can breathe air and water.

Legendary Resistance (4/Day, or 5/Day in Lair). If the dragon fails a saving throw, it can choose to succeed instead.

Actions

Multiattack. The dragon makes three Rend attacks. It can replace one attack with a use of Spellcasting to cast Melf's Acid Arrow (level 4 version).

Rend. Melee Attack Roll: +15, reach 15 ft. Hit: 17 (2d8 + 8) Slashing damage plus 9 (2d8) Acid damage.

Acid Breath (Recharge 5–6). Dexterity Saving Throw: DC 22, each creature in a 90-foot-long, 10-foot-wide Line. Failure: 67 (15d8) Acid damage. Success: Half damage.

Spellcasting. The dragon casts one of the following spells, requiring no Material components and using Charisma as the spellcasting ability (spell save DC 21, +13 to hit with spell attacks):

At Will: Detect Magic, Fear, Melf's Acid Arrow (level 4 version)
1/Day Each: Create Undead, Speak with Dead, Vitriolic Sphere (level 5 version)
Legendary actions
Legendary Action Uses: 3 (4 in Lair). Immediately after another creature's turn, the dragon can expend a use to take one of the following actions. The dragon regains all expended uses at the start of each of its turns.

Cloud of Insects. Dexterity Saving Throw: DC 21, one creature the dragon can see within 120 feet. Failure: 33 (6d10) Poison damage, and the target has Disadvantage on saving throws to maintain Concentration until the end of its next turn. Failure or Success: The dragon can't take this action again until the start of its next turn.

Frightful Presence. The dragon uses Spellcasting to cast Fear. The dragon can't take this action again until the start of its next turn.

Pounce. The dragon moves up to half its Speed, and it makes one Rend attack.

Black dragons delight in suffering and ruin. While other chromatic dragons scheme for power and wealth, these dragons seek to tear down all they see and rule over what remains. Black dragons are terrifying creatures with curved horns and withered visages suggestive of fiendish skulls. They typically inhabit stagnant swamps, crumbling ruins, or places of magical or environmental corruption. Their acid breath scars their domains, eroding the features from ancient statues and leaving nature with festering wounds. Black dragons hoard tarnished symbols of hope and relics of fallen empires. The more sought-after the treasure, the more black dragons prize it—particularly if they were responsible for it being lost.
Habitat: Swamp
Treasure: Relics
Monster Manual 2024 (BR)
  1. DnD 2024 Monsters › Ancient Black Dragon
Ancient Black Dragon