Image promptgargantuan ancient black dragon, skeletal sinister build, wet oil-black ridged scales flecked with corrosion, deep eye-ridges, long curving skull-like horns, receding fanged snout, hissing stream of caustic acid breath, corroded bone and sludge, looming from black water of fetid corrupted swamp, drowned cypress, reeking mist, half-submerged, glinting malevolent eyes, dark fantasy, grimdark, painterly digital art, dramatic chiaroscuro lighting, muted desaturated palette with corrupted-crimson accents, weathered post-Cataclysm atmosphere, intricate high detail, cinematic composition

Ancient Black Dragon

Gargantuan Dragon (Chromatic), Chaotic Evil
CR 21ControllerUnderground
AC 22
Initiative +16 (26)
HP 367 (21d20 + 147)
Speed 40 ft., Fly 80 ft., Swim 40 ft.
STR
27
+8
save +8
DEX
14
+2
save +9
CON
25
+7
save +7
INT
16
+3
save +3
WIS
15
+2
save +9
CHA
22
+6
save +6
Skills Perception +16, Stealth +9
Immunities Acid
Senses Blindsight 60 ft., Darkvision 120 ft.;
Languages Common, Draconic

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 Acid Arrow (level 4 version).

Rend. Melee Attack Roll: Hit: +15, reach 15 ft. 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- Failure: Success: wide Line. 67 (15d8) Acid damage. 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): Acid Arrow Detect At Will: (level 4 version), Magic Fear , Create Undead Speak with Dead Vitriolic 1/Day Each: , , 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 Failure: creature the dragon can see within 120 feet. 33 (6d10) Poison damage, and the target has Disadvantage on saving throws to maintain Concentration until the Failure or Success: end of its next turn. 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 Pudding Black Pudding