Medium monstrosity, neutral evil

Armor Class 12

Hit Points 42-54

Speed 40 ft.

STR DEX CON INT WIS CHA
16 (+3) 14 (+2) 13 (+1) 6 (-2) 12 (+1) 5 (-3)

Skills Perception +3, Stealth +6

Damage Resistances bludgeoning, piercing, and slashing from nonmagical attacks while in dim light or darkness

Senses darkvision 60 ft.

Challenge 2 (450 XP)

Ethereal Awareness. The shadow mastiff can see ethereal creatures and objects.

Keen Hearing and Smell. The shadow mastiff has advantage on Wisdom (Perception) checks that rely on hearing or smell.

Shadow Blend. While in dim light or darkness, the shadow mastiff can use a bonus action to become invisible, along with anything it is wearing or carrying. The invisibility lasts until the shadow mastiff uses a bonus action to end it or until the shadow mastiff attacks, is in bright light, or is incapacitated.

Sunlight Weakness. While in bright light created by sunlight, the shadow mastiff has disadvantage on attack rolls, ability checks, and saving throws.

Actions

Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 10 (2d6+3) piercing damage. If the target is a creature, it must succeed on a DC 13 Strength saving throw or be knocked prone.

Terrifying Howl The shadow mastiff howls. Any beast or humanoid within 300 feet of the mastiff and able to to hear its howl must succeed on a DC 11 Wisdom saving throw or be frightened for 1 minute. A frightened target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a target’s saving throw is successful or the effect ends for it, the target is immune to any shadow mastiff’s Terrifying Howl for the next 24 hours.