This creature has the body of a large dog, with a mouth full of sharp teeth and a smooth bluish-black coat that almost seems to drink in the light around it.
Shadow mastiffs are great hounds that prowl the night, seeking any prey they can find. Their native plane is a place of eternal shadow. Shadow mastiffs stand over 3 feet tall, with most weighing nearly 300 pounds.
Combat
Shadow mastiffs prefer fighting in shadows or dark conditions, which gives them a great advantage. If a magical light source negates the shadows around them, shadow mastiffs are cunning enough to either move out of the light or back off and break up the opposition with their baying. They have been known to seize and carry off items enspelled with daylight spells.
Shadow mastiff
Medium magical beast (extraplanar)
Init +6; Senses darkvision, scent; Perception +6
Defense
AC 16, touch 12, flat-footed 14 (+2 Dex, +4 natural)
hp 37 (5d8+15)
Fort +7, Ref +6, Will +4
Defenses shadow blend
Offense
Speed 50 ft.
Melee bite +9 (1d8+6 plus trip
Space 5 ft.; Reach 5 ft.
Special Attacks bay
Statistics
Str 19, Dex 15, Con 17, Int 4, Wis 12, Cha 13
Base Atk +5; CMB +9; CMD 21 (25 vs. trip)
Feats Improved Initiative, Iron Will, Spring Attack
Skills Perception +6, Stealth +10, Survival +6 (+10 to track by scent)
Languages Common (cannot speak)
Morale indomitable (+6)
Ecology
Environment Plane of Shadow
Organization solitary, pair, or pack (1d8+4)
Special Abilities
Bay (Su)
When a shadow mastiff howls or barks, all creatures within a 300-foot spread except evil outsiders must succeed at a DC 13 Will save or become panicked for 1d4+1 rounds. This is a sonic, mind-affecting fear effect. Whether or not the save is successful, an affected creature is immune to the same mastiff’s bay for 24 hours. The save DC is Charisma-based. If multiple shadow mastiffs bay together, only a single save is made by each affected creature, but the DC increases by 1 for each participating shadow mastiff.
Trip (Ex)
A shadow mastiff that hits with a bite attack can attempt to trip the opponent as a free action without provoking an attack of opportunity. If the attempt fails, the opponent cannot react to trip the shadow mastiff.
Shadow Blend (Su)
In any condition of illumination other than full daylight, a shadow mastiff disappears into the shadows, giving it concealment (50% miss chance). Artificial illumination, even a light or continual flame spell, does not negate this ability; a daylight spell, however, does. A shadow mastiff can suspend or resume this ability as a free action.