Adult Blue Dragon
Huge dragon, lawful evil
Armor Class 19 (natural armor)
Hit Points 212 (17d12 + 102)
Speed 40 ft., fly 80 ft., swim 20 ft., climb 20 ft., burrow 30 ft.
str
25 (+7)
dex
10 (+0)
con
23 (+6)
int
16 (+3)
wis
15 (+2)
cha
20 (+5)
Saving Throws Dex +5, Wis +7
Skills Perception +12, Stealth +5
Damage Immunities lightning
Senses blindsight 60 ft., darkvision 120 ft., passive Perception 22
Languages Common, Draconic
Challenge 16 (15,000 XP)
Legendary Resistance (3/Day, or 4/Day in Lair). If the dragon fails a saving throw, it can choose to succeed instead.
Actions
Lightning Breath. Dexterity Saving Throw: DC 19, each creature in a 90-foot-long, 5-foot-wide Line. Failure: 60 (11d10) Lightning damage. Success: Half damage.
Multiattack. The dragon makes three Rend attacks. It can replace one attack with a use of Spellcasting to cast Shatter.
Rend. Melee Attack Roll: +12, reach 10 ft. 16 (2d8 + 7) Slashing damage plus 5 (1d10) Lightning damage.
Spellcasting. 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 - **1/Day Each:** Scrying, Sending
Spellcasting (CHA, DC 18, +10 to hit)
At Will: Detect Magic, Invisibility, Mage Hand, Shatter
1/Day Each: Scrying, Sending
Attack Summary
Legendary Actions
The adult blue dragon can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The adult blue dragon regains spent legendary actions at the start of its turn.
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.