Living Shadow. While in dim light or darkness, the dragon has resistance to damage that isn’t force, psychic, or radiant.

Shadow Stealth. While in dim light or darkness, the dragon can take the Hide action as a bonus action.

Sunlight Sensitivity. While in sunlight, the dragon has disadvantage on attack rolls, as well as on Wisdom (Perception) checks that rely on sight.

Amphibious. The dragon can breathe air and water.

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

Bite. Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 17 (2d10 + 6) piercing damage plus 3 (1d6) necrotic damage plus 3 (1d6) fire damage.

Claw. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 13 (2d6 + 6) slashing damage.

Shadow Breath (Recharge 5–6). The dragon exhales shadowy fire in a 30-foot cone. Each creature in that area must make a DC 18 Dexterity saving throw, taking 56 (16d6) necrotic damage on a failed save, or half as much damage on a successful one on a failed save the target will also be delt 28 (8d6) fire damage.