Phantasm

Being far more powerful ghosts, phantasms are dependent on their original species for much of their composition. Unlike ghosts, much of the 'details' of their self have mutated, twisted, or otherwise become lost, turning the phantasm into a mass of roiling emotions and spiritual miasma. It is, overall, difficult to distinguish a phantasm from a ghost based purely on visuals, and other identifiers should be relied upon.

Intangible – They have no corporeal form, and so mundane materials have almost no affect against them. Magical attacks and mana-infused objects are necessary to interact with their purely mana-comprised existence.   Undead Endurance – Driven by their metabolized mana, they can keep going for absurd amounts of time. In fact, the only time they stop is when they've lost all their mana, or lost track of their prey.   Life Sense – They can sense the presence of the living in a supernatural manner. This means despite loss of critical sensory organs, like eyes or ears, they can still track their targets with disturbing precision.   Possession – The strength of the phantasm allows them to possess living beings or inanimate objects; the latter is far easier for them. Despite whatever happens to their possessed thing, the phantasm doesn't suffer damage–but they can become trapped in it.

If ghosts are departed people, phantasms are the heinous offspring of their lingering emotions. Like a parasite leaving their host, phantasms acquire a will of their own, a desire to torment and devour the living to bring themselves into corporeal existence. As a zahmka undead, their intellect is frighteningly capable in utilizing their strengths. For many people, it is hard to tell if bad luck or worse stalks them, for their own minds begin turning against them. Nightmares plague their sleep, voices haunt their ears just out of recognition, an ever persistent headache, an itching crawl down their skin that no scratching solves--all of it, very typical of a phantasm haunting.   It is not strictly enough to kill, for they do not wish to destroy a person's body. A phantasm tortures and drives to insanity, delighting in the suffering of their victims. Only when they are truly shattered apart do they begin the possession, taking control as easily as one slips into a suit of armor. From there, the goals may differ exactly but every phantasm diligently works to bring ruin forth. Whether of a family or a nation, they do not distinguish in who or how much suffering. Among the zahmka undead, they are the most taken with strange mannerisms, but it is difficult to deny the damage they can inflict.   A 'wild' phantasm is certainly problematic, but their true reputations arise in the servitude of Grave Queens/Kings, nekrokin, and necromages. Bound to serve far more focused and purposeful wills, phantasms become finely tuned weapons of sabotage and subterfuge. When not for that, they become phantasmal soldiers bound to suits of armor and weapons, virtually indestructible to any mundane weapons. For as much as they hate their own imprisonment in this lifestyle, they delight more in the tasks they're set to.