Many believe ghosts to be real. Souls of dead people who still have unfinished business in the land of the living and thus unable to pass on into the afterlife. They remain bond to the places of emotional attachment, haunting them, scaring the hell out of eventual passersby and patiently waiting for their current situation to take a turn for the better.
Some people think ghosts are a mere hallucination, a mind trick happening to the emotionally unstable. Hard to believe in this, especially when said mind trick starts to attack all of a sudden, causing terrible headache and ripping the very soul to shreds with its unbearable mental pressure.
Specter is immune to physical damage.
Damage dealt by Specter is magical.