I spent way too long on this omg.

Category 1: Friendly, benevolent, interact with people out of desire to maintain semblance of life they lost.
Category 2: Largely harmless, minimal interaction with humans. Frequently mischievous.
Category 3: Commonly confused with the idea of ‘guardian angels’. Exist to protect loved ones who still live or to right wrongs committed against the haunting spirit in life. Dangerous only to specific targets (varies with ghost).
Category 4: Mischievous to dangerous levels. Will try to fool the living into deals that benefit only the spirit.
Category 5: Spirits that died a violent death. Harbor extreme jealousy towards the living and will kill those who summon them. Are contained to one type of object - cannot manifest outside of said object’s bounds.
Category 6: Spirits that died a violent death and were unable to comprehend their loss of life (frequently children). Erratically playful and vengeful in behavior. Will kill anyone who they deem a threat or see as not playing by their rules. Can not stray far from site of their death.
Category 7: Malevolent spirits who died violently and want others to suffer as they do. Frequently bound to certain objects, but can exercise psychic influence over those around them. Some possess ability to hijack human vessels.
Category 8: Similar to Category 6 ghosts, but will kill indiscriminately. Frequently haunt one large area and goes through periods of ‘hibernation’ between murders.
Category 9: (Not pictured) Use dreamscape to capture victims. Sole purpose for existence is to kill. Can be temporarily contained, but never destroyed.
Category 10: (Not pictured) PRAY FOR MERCY