Slow shadow

Slow shadows were a rare type of undead not native to the Prime Material plane and possibly related to the undead known as shadows.

Description
These creatures had the appearance of an undulating, inky blob with amorphous twisting to their outlines that made their size fluctuate between. Despite their name, slow shadows did not move at a slow pace. They were nearly invisible in dusky or moderate light.

Behavior
Slow shadows had a low level of intellect.

Abilities
The touch of a slow shadow was very chilling and caused creatures to be slowed. They continuously impart a harmful sense of cold upon creatures they touched, draining them of their positive energy. If killed by them, a humanoid would transform into a slow shadow itself within a day, though this process was expediated in areas exposed to negative energy.

Slow shadows were impervious to harm from cold and lightning. They were also unaffected by holy water, charm, hold, command undead, and turn undead. If directed at them the spell haste would drive them away, though it was ineffective once they started grappling prey. They could only be harmed by weaponry with a +2 or greater enchantment.

Combat
These creatures typically sneaked up on and surprised their prey. They sometimes withdrew into surrounding cracks and corners, waiting for their prey to pass by.

Ecology
Little was known about how these creatures interacted with each other and there had been no recorded, successful attempts to communicate with them. Those created from being killed by another slow shadow would generally stay within of the site of their death.

Diet
These creatures preyed upon the positive energy of other creatures, including demihumans and humans.

Habitats
Slow shadows were typically found in dark, shadowy places such as ruins and underground tunnel complexes. They were native inhabitants of the Negative Energy plane, but could also be found on the Plane of Shadows and in the Domains of Dread. Beyond Toril, this type of undead occurred on the planet Oerth.

Scholars on the Prime Material plane could agree that they were not native to their plane, though were unable to ascertain whether they were native to the Negative Energy plane or the Plane of Shadows.

Relationships
These undead acted as servants of the death deity Jergal.

Some evil-aligned clerics seemed to be capable of enslaving and controlling slow shadows.