Necrokinetic Mist

There aren't many things that scare necromancers, but necrokinetic mist is one of them. A light lavender fog released found in underground pockets in places of intense necromantic energy, necrokinetic mist seems naturally drawn to the undead, though prolonged exposure is dangerous for living beings as well. The strange substance seems to naturally leak into creatures animated by necromantic energy, causing an enormous increase in strength and durability along with a burst of intense rage. The mist can be released via cave-ins or other natural phenomena, and there are rumors of attempts to locate and mine such pockets by the alchemists of Highspire.
If affected, basic undead like skeletons and zombies automatically break free of their controllers (if any) and begin rampaging through the area. They attack anything and everything with no regard for self-preservation. Intelligent undead receive a saving throw to fight off the effects, but if they fail then they manifest similar behavior.
While they prioritize living targets and won't attack other undead possessed by the mist, those possessed by necrokinetic mist are also willing to attack non-possessed undead, constructs or even the surrounding terrain if nothing else is available. That said, there are rumors of undead possessed for longer periods calming down and even acting towards some collective purpose. Whether the mist controls all undead towards some ultimate goal or the actions of the possessed are merely the random consequences of a chemical process has so far been impossible to determine.
Research using necrokinetic mist is difficult, as it easily loses its properties when removed from unhallowed or necromantically charged areas. Nonetheless, some magitech scientists are rumored to be working towards synthesizing a compound with similar properties in the hopes of developing a weapon against masses of undead.
Necrokinetic mist is rare, and some necromancers even consider it an old wive's tale. The chaos it can cause for even the strongest of necromancers is all too real, however, and more than one wizard exploring a ruin with their pet zombies has had to flee for their lives when their mindless puppet went berserk.

Properties

Material Characteristics

A light lavender color, this thin mist is often mistaken for a trick of the light when it first appears. While not mobile under its own power, the mist begins drifting towards any necromantic energy within 150 feet or so. Wind can keep the fog at bay or move it around as normal, but the slow, almost magnetic attraction to undead will continue as long as they remain in proximity.

Physical & Chemical Properties

Necromantic spells cast in or into the fog may be empowered, at the GM's discretion, but any spell that requires the caster to control or direct energy requires a check against the mist's dc to avoid losing control of the spell.
Necrokinetic mist allows a save by intelligent undead proportional to the strength of the local necromantic energy (i.e. DC will depend on GM's decision). Living creatures exposed to the mist take one point of damager per hit die for each hour of exposure without leaving the mist for at least ten minutes, and must make a saving throw or gain a level of exhaustion.
The mist begins dissolving in sunlight (see below) and will not enter a sunlit area unless it has no choice (i.e. a very powerful wind). This refusal to enter a situation that would lead to its dissolution features as one of the stronger arguments by theoretical mages that necrokinetic mist possesses some rudimentary form of consciousness.

Compounds

While it does not naturally "mix" with any known substance, necrokinetic mist often blends in with regular banks of fog or mist, making it more difficult to spot. In theory, the mist ought to be found in liquid form as well, but so far there have been no confirmed sightings of such a phenomenon.

Geology & Geography

Necrokinetic mist tends to appear in areas with powerful necromantic energy that are unhallowed or otherwise aligned to the undead. Because of its aversion to sunlight, it's often found in perpetually misty areas like lakes and frequently appears underground or in seaside caves.

Origin & Source

Unknown

Life & Expiration

Necrokinetic mist does not naturally decay, but if the source of the local necromantic energy field is destroyed or dispelled it slowly evaporates over a week, or in a little less than two days of exposure to direct sunlight. Necrokinetic mist strong enough to be out in sunlight is almost unheard of, so the substance tends to remain penned indoors or underground

History & Usage

Industrial Use

Necrokinetic mist would make a powerful weapon of industrial sabotage to any organization or group that depends upon undead for slave labor.

Distribution

Storage

To keep it from losing its properties, the mist must be trapped within necrotempered glass and stored out of direct sunlight in a chilled container.

Law & Regulation

Though not actually mentioned by name, most countries that allow undead consider anyone transporting the mist without a damn good excuse a potential terrorist.

Type

Elemental / Molecular

Value

To an alchemist or magitech scientist who's heard of the mist, it would be extremely valuable. The lack of interest of everyone else might compromise a seller's bargaining power, however.

Rarity

Rare

Odor

The few accounts of those who've survived the mist suggest it smells faintly of incense.

Taste

A faint taste of mint after prolonged exposure. Living beings will gradually find their extremities going numb, starting at the tips of fingers and toes and slowly proceeding up the body.

Color

Light lavender to dark purple