Ancient Black Dragon
Source: SRD / Basic Rules
title: Ancient Black Dragon
*Gargantuan dragon, Chaotic Evil*
- **Armor Class** 22 (natural armor)
- **Hit Points** 367 (`21d20 + 147`)
- **Speed** 40 ft., fly 80 ft., swim 40 ft.
|STR|DEX|CON|INT|WIS|CHA|
|:---:|:---:|:---:|:---:|:---:|:---:|
|27 (+8)|14 (+2)|25 (+7)|16 (+3)|15 (+2)|19 (+4)|
- **Proficiency Bonus** +7
- **Saving Throws** Dexterity +9, Constitution +14, Wisdom +9, Charisma +11
- **Skills** Perception +16, Stealth +9
- **Senses** blindsight 60 ft., darkvision 120 ft., passive Perception 26
- **Damage Immunities** acid
- **Languages** Common, Draconic
- **Challenge** 21
## Traits
***Amphibious.*** The dragon can breathe air and water.
***Legendary Resistance (3/Day).*** If the dragon fails a saving throw, it can choose to succeed instead.
## Actions
***Multiattack.*** The 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 15 ft., one target. *Hit:* 19 (`2d10 + 8`) piercing damage plus 9 (`2d8`) acid damage.
***Claw.*** *Melee Weapon Attack:* `+15` to hit, reach 10 ft., one target. *Hit:* 15 (`2d6 + 8`) slashing damage.
***Tail.*** *Melee Weapon Attack:* `+15` to hit, reach 20 ft., one target. *Hit:* 17 (`2d8 + 8`) bludgeoning damage.
***Frightful Presence.*** Each creature of the dragon's choice that is within 120 feet of the dragon and aware of it must succeed on a DC 19 Wisdom saving throw or become [frightened](rules/conditions.md#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 dragon's Frightful Presence for the next 24 hours.
***Acid Breath (Recharge 5-6).*** The dragon exhales acid in a 90-foot line that is 10 feet wide. Each creature in that line must make a DC 22 Dexterity saving throw, taking 67 (`15d8`) acid damage on a failed save, or half as much damage on a successful one.
## Legendary Actions
***Detect.*** The dragon makes a Wisdom ([Perception](rules/skills.md#Perception)) check.
***Tail Attack.*** The dragon makes a tail attack.
***Wing Attack (Costs 2 Actions).*** The dragon beats its wings. Each creature within 15 feet of the dragon must succeed on a DC 23 Dexterity saving throw or take 15 (`2d6 + 8`) bludgeoning damage and be knocked [prone](rules/conditions.md#prone). The dragon can then fly up to half its flying speed.Environment
swamp