Psy Pseudodog (5e Creature)
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Medium beast, unaligned
Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 5 (1d4 + 3) piercing damage.
Phantom. The psy pseudodog creates three phantoms in spaces adjacent to it. These phantoms have the properties of a pseudodog, but disappear if any damage is dealt to them. If a phantom attacks a creature, the creature must first make a DC 16 Intelligence or Wisdom saving throw or take 5 (1d4 + 3) psychic damage. On a successful save, the creature realizes that the phantoms are not real and does not receive damage from this attack and will not receive damage from any of the phantoms' attacks for the next hour. These phantoms cannot be seen by a creature immune to psychic damage.
Some pseudodogs mutated to possess psy powers of unknown origin. These are called psy pseudodogs. They can control a person's mind, causing them to see phantom pseudodogs, which seem so lifelike, that their bites actually cause pain. If one concentrates enough, he can become free of the phantoms.