Faithful Hound

You conjure a phantom watchdog in an unoccupied space you can see within range of the spell, where it remains for the duration, until dismissed as an action, or until you move more than 100 feet away from it.

The hound is invisible to all creatures except you and can’t be harmed. When a Small or larger creature comes within 30 feet of the hound without first speaking the password you specify when you cast the spell, it starts barking loudly. The hound sees invisible creatures and can see into the Spiritual Realm. It ignores illusions.

At the start of each of its turns, the hound tries to bite a creature hostile to you that is within 5 feet of it. The hound’s attack bonus equals your spellcasting ability modifier plus your proficiency bonus. On a hit, it deals 4d8 piercing damage.