I wanted to include a Poltergeist in one of my encounters but I’m not entirely sure how to handle one thing in its stat block.
The Poltergeist can use its Telekinetic Thrust ability to toss a creature up to 30 feet, and that creature takes 1d6 damage per 10 feet moved if it hits a “hard surface or heavy object”. It also says it can hurl objects at creatures and they take 2d4 damage on hit. The text is below:
Telekinetic Thrust. The poltergeist targets a creature or unattended object within 30 feet of it. A creature must be Medium or smaller to be affected by this magic, and an object can weigh up to 150 pounds.
If the target is a creature, the poltergeist makes a Charisma check contested by the target’s Strength check. If the poltergeist wins the contest, the poltergeist hurls the target up to 30 feet in any direction, including upward. If the target then comes into contact with a hard surface or heavy object, the target takes 1d6 damage per 10 feet moved.
If the target is an object that isn’t being worn or carried, the poltergeist hurls it up to 30 feet in any direction. The poltergeist can use the object as a ranged weapon, attacking one creature along the object’s path (+4 to hit) and dealing 5 (2d4) bludgeoning damage on a hit.
The Monster Manual reads that the Poltergeist is more driven by rage than anything else, and I was planning on playing it as blindly attacking the party by flinging objects at them or pushing them away. That said, it seems at least possible that it could throw one PC into another. How should I rule this? Should only the tossed creature take damage? The PC that was hit? Both?