Besnick Dog

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

Pounce. If the tiger moves at least 20 feet straight toward a creature and then hits it with a claw attack on the same turn, that target must succeed on a DC 14 Strength saving throw or be knocked prone. If the target is prone, the tiger can make one bite attack against it as a bonus action.

Bite. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 4 (1d6 + 1) piercing damage.

Paws. Melee Weapon Attack: +6 to hit, reach 6 ft., one target. Hit: 12 (2d6 + 5) slashing damage.

The Besnick Dog can use each legendary action once every long rest.

Power Word Heal. Range: touch. A  wave of healing energy washes over the creature the besnick dog touches. The target regains all its hit points. If the creature is charmed, frightened, or stunned, the condition ends. If the creature is prone, it can use its reaction to stand up. This spell has no effect on undead or constructs. 

Heroism. Range: self. Casting time: 1 action. Duration: concentration, up to 1 minute. A willing creature touched by a besnick dog is imbued with bravery. Until the spell ends the creature is immune to being frightened and gains [Tooltip Not Found] equal to the Charisma modifier at the start of each of the creature's turn. When the spell ends, the target loses any remaining temporary hit points from this spell. 

Staggering Smite. Range: self. Casting time: 1 bonus action. Duration: concentration, up to 1 minute. The next time a besnick dog hits a creature with a melee weapon attack during this spell's duration, the attack pierces both body and mind, and the attack deals a 4d6 psychic damage to the target. The target must make a Wisdom saving throw. On a failed save, it has a disadvantage on attack rolls and ability checks, and can't take reactions, until the end of its next turn.