Monster
Adult Blue Dragon
Official reference · XMM · 2024
- Creature type
- Dragon
- Size
- Huge
- Armor class
- 19
- Hit points
- 212 (17d12 + 102)
- Speed
- Walk 40 ft., Burrow 30 ft., Fly 80 ft.
- Challenge rating
- 16
- Alignment
- Lawful Evil
- Strength
- 25
- Dexterity
- 10
- Constitution
- 23
- Intelligence
- 16
- Wisdom
- 15
- Charisma
- 20
- Passive Perception
- 22
- Initiative
- +10
- Saving Throws
- dex: +5; wis: +7
- Skills
- perception: +12; stealth: +5
- Senses
- Blindsight 60 ft., Darkvision 120 ft.
- Languages
- Common, Draconic
- Immunities
- lightning
Traits
Legendary Resistance (3/Day, or 4/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 Shatter.
Rend
Melee Attack: +12, reach 10 ft. Hit: 16 (2d8 + 7) Slashing damage plus 5 (1d10) Lightning damage.
Lightning Breath (Recharge 5–6)
Dexterity Saving Throw: DC 19, each creature in a 90-foot-long, 5-foot-wide Line. Failure: 60 (11d10) Lightning damage. Success: Half damage.
Legendary action uses: 3 (4 in its lair). The creature can use one option at the end of another creature’s turn and regains spent uses at the start of its turn.
Legendary actions
Cloaked Flight
The dragon uses Spellcasting to cast Invisibility on itself, and it can fly up to half its Fly Speed. The dragon can't take this action again until the start of its next turn.
Sonic Boom
The dragon uses Spellcasting to cast Shatter. The dragon can't take this action again until the start of its next turn.
Tail Swipe
The dragon makes one Rend attack.
The dragon casts one of the following spells, requiring no Material components and using Charisma as the spellcasting ability (spell save DC 18):
At will: Detect Magic, Invisibility, Mage Hand, Shatter
Regional effects
The region containing an adult or ancient blue dragon's lair is changed by its presence, creating the following effects:
- Sinkholes: Sinkholes form more frequently in the area within 1 mile of the lair. Whenever a creature in that area other than the dragon and its allies finishes a Long Rest, roll 1d20. On a 1, a sinkhole opens beneath the creature, and the creature must succeed on a DC 15 Dexterity saving throw or fall 2d4 × 10 feet into the sinkhole.
- Spiteful Storms: Dust devils and thunderstorms rage within 1 mile of the lair. The area is Lightly Obscured.
If the dragon dies or moves its lair elsewhere, these effects end immediately.