Possibly trapped souls, possibly 'echoes of the aura', ghosts are the restless dead still kicking around on earth. Oftentimes they are more frequent if the person died a violent death or if there is strong preternatural force involved with their death or in the area after their death.
Generally, a ghost will not stray far from where it died or where its mortal remains are buried, nor can it do much other than create a very slightly cold spot and perhaps make faint whispering, dim shadowy images, and a slight creep up the spine in the dark of night. If a person pays attention to these slight hints (for more than two or three poses), the ghost can upgrade to a more humanoid form with a faint glow, the occasional speaking-level phrase, and a rather notable 'pins and needles' sensation. If still acknowledged, soon the form is quite identifiable as a stylized form of the dead person who can speak normally and manipulate objects to a very slight degree (candles may flicker, hair brushed about, but nothing actually moved that is more stable than dust, hair, or paper). This trend can increase with the continued acknowledgment of the ghost's presence, up to full-on poltergeist effects. The ghost can also stray from its haunt as long as someone is sustaining it.
|Stage 0||Nothing can exactly be seen of the ghost itself. Just a faint feeling along the spine, a chill, and perhaps the faintest of distortion of air in the light and the faintest of glows in the dark. (generally this requires either a Sensitivity to ghosts, or for the ghost to want to manifest)|
|Stage 1||Nothing can clearly be seen of the ghost itself. Just a chill feeling along the spine, a cold spot, and a waver of an image glowing faintly in the night and flickering like a dust devil during the day. If directly addressed, perhaps a whisper that could be dismissed as the wind. No physical contact can be made.|
|Stage 2||The ghost is a dim flicker in the air like a poorly projected image. A tingle of cold in the air and a prickling along the thumbs, scalp, and spine of those nearby make the presence clearly detectable. In shadows it is clearly a human form, the face more distinct in the details while the limbs trail off. In the light it is more a standing shadow with feature obscured. If directly addressed, a word or two is caught here and there. Physical contact is restricted to candles flickering, dust shifting, but nothing more than what a passing light breeze may cause.|
|Stage 3||The ghost is a distinct flicker in the air like a projected image. A tingle of cold in the air and a prickling along the thumbs, scalp, and spine of those nearby make the presence clearly detectable. In shadows it is clearly a glowing translucent human form, the face and form quite distinct in the details with only the finer details of the clothing lost. In the light it is more a standing shadow with a recognizable face, the limbs fading to obscurity. If directly addressed, a sentence or two is caught here and there. If the spirit wishes, candles may flicker while paper and hair may drift, as if a gust of a wind were focused about. Direct contact is just a passing sense, like a fine-haired paintbrush drawn across the skin.|
|Stage 4||The ghost is a projected image of distinct clarity. A tingle of cold in the air and a prickling along the thumbs, scalp, and spine of those nearby make the presence clearly detectable. In shadows it is clearly a glowing translucent human form, the face, form, and details of the clothing quite distinct. In the light it is perhaps more disturbing than in the dark for the figure is clearly there, yet clearly not solid. If directly addressed, it can directly reply. The ghost can physically interact with people and things as if they were solid or as if they weren't there at all (up to the ghost's choosing)|
Animators performing Zombie Raisings in the area tend to make ghosts manifest at a faster rate, as do Necromancers who aren't even doing anything to make the ghosts act up. No matter how they manifested, a ghost's abilities will start to fade once folks leave the area or start to ignore them (which can be very tricky if they're manifested enough).
Oftentimes, ghosts are just "echoes" of their living selves, not really able to think new thoughts or deviate from previous behaviour. These echoes often seem to have large quantities of limestone, marble, or quartz nearby (possibly having to do with a recorded piezoelectric pattern, and possibly the reasoning behind those minerals being popular for gravestones). One hypothesis is that ghosts can only sense things that the living have forgotten. Rare is the ghost that is the person "living on beyond death" like a vampire or a particularly well revived zombie. The shifter Munin are about the closest one can get to a sentient ghost. The invention of the modern Ouija board in the 1890s helped to spread the urban myth of 'chatty ghosts'.
Due to all this, ghosts can not be player characters (but folks can attempt to RP them as NPCs if they do so with caution and self-restraint).