Black Dragon Wyrmling

5e compatible shield

Medium dragon, chaotic evil

Armor Class 17 (natural armor)
Hit Points 33 (6d8 + 6)
Speed 30 ft., fly 60 ft., swim 30 ft.

STR DEX CON INT WIS CHA
15 (+2) 14 (+2) 13 (+1) 10 (+0) 11 (+0) 13 (+1)

Saving Throws Dex +4, Con +3, Wis +2, Cha +3
Skills Perception +4, Stealth +4
Damage Resistances 
Damage Immunities acid
Condition Immunities 
Senses blindsight 10 ft., darkvision 60 ft., passive Perception 14
Languages Draconic
Challenge 2 (450 XP)

Amphibious. The dragon can breathe air and water.

Actions

Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 7 (1d10 + 2) piercing damage plus 2 (1d4) acid damage.

Acid Breath (Recharge 5–6). The dragon exhales acid in a 15-foot line that is 5 feet wide. Each creature in that line must make a DC 11 Dexterity saving throw, taking 22 (5d8) acid damage on a failed save, or half as much damage on a successful one.