Ghostly Malevolence!

[Dagredhel]

When a ghost with the malevolence ability possesses a creature, and that creature is successfully attacked and damaged, does it harm the ghost? Which hit point total is used, the ghost's or the possessed creature's? If it is the ghost's, is it modified for the Constitution of the possessed? If the possessed creature is slain, is the ghost affected beyond the loss of a material vessel? (Is the ethereal ghost hurt by damage to the material body it usurps?)

 

[AuraSeer]

As the description says, it works like a Magic Jar spell. Attacks damage the hp of the possessed creature, without harming the ghost.

 

[Dagredhel]

Not so fast!!!

The Magic Jar description (from the SRD) states...

"If successful, the character's life force occupies the host body, and the host’s life force is imprisoned in the magic jar. The character keeps most mental abilities and gains some physical abilities, as with polymorph other (except that the character gets the creature’s actual physical abilities, not average ones)."

And the Polymorh Other description reads...

"The subject retains its Intelligence, Wisdom, and Charisma scores, level and class, hit points (despite any change in its Constitution score), alignment, base attack bonus, and base saves. (New Strength, Dexterity, and Constitution scores may affect final attack and save bonuses.)"

From this, it would seem to follow that the ghost uses its own hit point total, modified by the Constitution of the creature it is possessing, which brought up my question in the first place.

 

[AuraSeer]

Read the FAQ.

How many hit points do you have when you take over another body with a magic jar spell? What if the body you take over is damaged?

In the case of magic jar, hit points go with the body. When you possess a body, you have whatever hit points that body has at the time.