Young Mercury Dragon (5e Creature)
From D&D Wiki
Young Mercury Dragon
Large dragon, chaotic good
Saving Throws Dex +5, Con +6, Wis +5, Cha +5
Amorphous. The dragon can move through a space as narrow as 1 inch wide without squeezing.
Multiattack. The dragon makes three attacks: one with its bite and two with its claws.
Bite. Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 15 (2d10 + 4) piercing damage.
Claw. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 11 (2d6 + 4) slashing damage.
Breath Weapons (Recharge 5-6). The dragon uses one of the following breath weapons:
Poison Breath. The dragon exhales poison in a 40-foot cone. Each creature in that area must make a DC 14 Constitution saving throw, taking 40 (9d8) poison damage on a failed save, or half as much damage on a successful one.