The slithering tracker is a transparent slime monster, similar in nature to the gelatinous cube but smaller and more amorphous. A slithering tracker is 95% undetectable under normal circumstances. When one encounters a possible victim (any living creature), the monster will follow at a distance until its chosen target sleeps. Then it will attack, touching the sleeping victim, who must save vs. Paralysis or be immobilized for 2d8 turns. The slithering tracker then drains the victim’s bodily fluids, doing 1d6 points of damage per turn in this way until the victim dies.

Slithering trackers live in dungeons, ruins and dark places. They are transparent and if not in natural sunlight are almost impossible to see (1 in 20 chance of spotting). They almost never attack their prey immediately, instead following and waiting until their target is asleep. They can follow through almost anything, being amorphous in shape and capable of seeping through tiny gaps, such as door jambs or cracks in stonework. If a slithering tracker catches its victim asleep, it will touch it, forcing the victim to roll a saving throw vs paralysation or be totally paralysed for 1d6 hours. The tracker will then feed directly on its victim’s life energy, killing it in 1 hour.