HAUNT

Damage Resistance. A haunt has damage resistance of DR +1/silver. Magic or silver weapons will do only 1 point of damage plus 1 point per magical plus of the weapon (no other adjustments apply). A haunt brought to 0 hit points will be dis-incorporated for 1 week before reforming at full strength in the area it is tethered.

Dexterity Damage. [fear] A haunt that touches a living creature with a contact attack will cause 2 points of Dexterity damage to a minimum of 0 (no save). A creature that is left with a 0 Dexterity is paralyzed. Creatures that suffer Dexterity damage feel a spreading numbness in their limbs. Dexterity points are regained at a rate of 1 point per 10 rounds of rest.

Magic Jar. (major) Any creature with an Animal Intelligence rating or higher in melee range with a 0 Dexterity can be possessed by the haunt (no save). The haunt gains control of the body and it's physical characteristics (Strength, Constitution, Dexterity), but not mental (the haunt retains it's own Intelligence, Wisdom, Charisma; i.e. mindlessness). The possessed body will retain it's original hit points and attacks damage the body not the haunt. Once a body is possessed, it will mindlessly attempt to complete the action for which the haunt was generated. Being mindless, a haunt can use any natural attacks of the possessed creature, otherwise it will use weapons (with a -2 non-proficiency penalty; any weapon use it had in life has been forgotten). If a possessed body becomes unconscious due to damage or dies, the haunt is forced to vacate the body (and will be tethered to that area going forward). 

If previously Good or Evil, a haunt will still have a vestige of their former alignment—if a creature with the opposite alignment (good vs. evil) is drained of Dexterity, instead of possessing it, the haunt will attempt to strangle it. Each round, as a complex activity, the haunt will strangle the victim. The first round will do 1 point of damage, the 2nd round, 2 points of damage, the 3rd round, 4 points of damage and the damage will continue to double each round until the creature dies. During this time, the haunt will ignore attacks or other creatures. 

Once the haunt's task is complete, it will exit the possessed creature and fade away. The possessed creature will be left without memory of the events and with a 3 Dexterity score (these are regained as described above). A possessed creature can also be freed using a (successful) exorcism spell (this will destroy the haunt forever).

Resistances. Haunts are immune to energy attacks other than fire. Non-magical fire does 1 point of damage per application and magical fire will do full damage.

Tethered. A haunt is tethered to the place where it died and cannot move past 60 feet from that spot unless inhabiting a possessed body.

Vulnerability to Hold Person. A possessed body that is targeted with a hold person spell will cause the haunt to be expelled immediately (no save). The possessed creature is not otherwise affected by the hold person spell.

The haunt is the spirit of a person who died before completing some vital task. A haunt inhabits an area within 60 feet of where its body died and never leaves this area. (Note—a haunt in possession of a material body can in fact leave its area and must do so in order to finish its task.) It desires but one thing its final rest. To accomplish this, it must possess a living creature and finish the task that prevents it from achieving everlasting slumber. A haunt only attacks humanoid creatures.

A haunt attacks with its touch. It concentrates on a single foe, attempting to render it helpless by draining its Dexterity. Once that victim reaches Dexterity 0, the haunt uses its magic jar ability to possess the body and then attempts to complete the task that binds it to this plane. If the haunt is attacked while possessing a body, it uses any natural physical abilities of the host to defend itself.

While a haunt is mindless, it may yet speak, mumbling things to itself—this may provide a clue to those facing it as to the nature of its final task.