# Ancient Blue Dragon

*Gargantuan Dragon (Chromatic), Lawful Evil*

- **Armor Class:** 22
- **Hit Points:** 481 (26d20 + 208)
- **Speed:** 40 ft., Burrow 40 ft., Fly 80 ft.
- **Initiative**: +4 (14)

|STAT|SCORE|MOD|SAVE|
| --- | --- | --- | ---- |
| STR | 29 | +9 | +9 |
| DEX | 10 | +0 | +7 |
| CON | 27 | +8 | +8 |
| INT | 18 | +4 | +4 |
| WIS | 17 | +3 | +10 |
| CHA | 25 | +7 | +7 |

- **Immunities**: Lightning
- **Skills**: Perception +17, Stealth +7
- **Senses**: blindsight 60 ft., darkvision 120 ft.; Passive Perception 27
- **Languages**: Common, Draconic
- **CR** 23 (XP 50,000, or 62,000 in lair)

## Traits

***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 *Shatter* (level 3 version).

***Rend.*** *Melee Attack Roll:* +16, reach 15 ft. 18 (2d8 + 9) Slashing damage plus 11 (2d10) Lightning damage.

***Lightning Breath (Recharge 5-6).*** *Dexterity Saving Throw*: DC 23, each creature in a 120-foot-long, 10-foot-wide Line. *Failure:*  88 (16d10) Lightning 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 22):

- **At Will:** *Detect Magic*, *Invisibility*, *Mage Hand*, *Shatter*
- **1e/Day Each:** *Scrying*, *Sending*

## 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* (level 3 version). The dragon can't take this action again until the start of its next turn.

***Tail Swipe.*** The dragon makes one Rend attack.

