Young Blue Dragon

Large, dragon, lawful evil

CR 9AC 18HP 152 (16d10)

Speed fly 80 ft, walk 40 ft, burrow 20 ft

str: 21; (+5)
dex: 10; (+0)
con: 19; (+4)
int: 14; (+2)
wis: 13; (+1)
cha: 17; (+3)

Saving Throws CHA +7, CON +8, DEX +4, WIS +5

Skills stealth +4, perception +9

Damage Immunities lightning

Senses blindsight: 30 ft., darkvision: 120 ft., passive_perception: 19

Languages Common, Draconic

Actions

Multiattack. The dragon makes three attacks: one with its bite and two with its claws.

Bite. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 16 (2d10 + 5) piercing damage plus 5 (1d10) lightning damage.

Claw. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 12 (2d6 + 5) slashing damage.

Lightning Breath. The dragon exhales lightning in an 60-foot line that is 5 feet wide. Each creature in that line must make a DC 16 Dexterity saving throw, taking 55 (10d10) lightning damage on a failed save, or half as much damage on a successful one.