Cargo Creep

Molecular Mimicry (Ex) As a standard action, a cargo creep can alter its physical composition to match a material within reach of its tentacle. When it does so, it gains a specific benefit and a vulnerability to a specific energy type based on the material. In addition, the cargo creep gains a +4 circumstance bonus to Disguise and Stealth checks when attempting to imitate or hide among that material, such as disguising itself as a metal plate in metallic form or hiding among plants in vegetation form. A cargo creep can match one of the following materials and can revert back to its default flesh state as a move action. The above cargo creep begins in its flesh state.
Flesh: When a cargo creep touches the flesh, fur, scales, or other skin covering of a creature, it gains a +2 circumstance bonus to Reflex saving throws and a vulnerability to acid.
Metallic: When a cargo creep touches worked metal, it gains DR 5/adamantine and a vulnerability to electricity.
Mineral: When a cargo creep touches natural, nonworked minerals such as stones and gems, it gains a +1 circumstance bonus to KAC and a vulnerability to sonic.
Synthetic: When a cargo creep touches material like fibers, plastics, and polymers, it gains a +1 circumstance bonus to EAC and a vulnerability to cold.
Vegetation: When a cargo creep touches natural plant matter (including that of plant creatures) or worked wood, it gains a +2 circumstance bonus to Fortitude saving throws and a vulnerability to fire.

The exact origin of cargo creeps is a mystery, though those who have seen them understand they are nuisances to crews of transport ships, especially those carrying the types of perishable goods that cargo creeps find delicious. A cargo creep vaguely resembles a cephalopod, with four large eyes and five tentacles that it uses for locomotion. The unusual cells in its skin allow a cargo creep to mimic any sort of material with uncanny accuracy, almost down to its molecular structure. This allows a cargo creep to hide almost anywhere and easily slip into cargo holds in search for food. A cargo creep is generally quick to hide or flee at the first sign of danger, except when cornered, at which point it strikes out at anything that gets too close.