Binomen Caederus mexicana
Average height 3 ft.
Sapience Non-Sapient
Aggressivity Extreme
Habitat Desert
Diet Carnivorous
Lifespan 24-72 hrs.
Subspecies None
Status Critically Endangered
Behind the Scenes
Universe Tremors
Performed by Mixture sounds of pigs and camels

Shriekers are bipedal carnivores that hunt by sensing the heat signature of their prey.


Shriekers are the second stage of the graboids' lifecycle. Eventually a mature graboid will burrow to the surface, beaching itself like a whale above the ground. At that point 3-6 shriekers will begin to eat their way out of the creature, killing it as they are born. Like graboids, they lack eyes and have a large beak; unlike graboids, they cannot detect vibrations and usually hunt in packs. Instead shriekers possess two flaps of skin on top of their skull that open up, allowing them to detect the body heat of their prey. If they sense heat they will scream (hence their name). While the sound serves no purpose, it does release a large amount of heat, acting like a flare for the rest of the pack. They will also attack any object that emits heat, such as a warm car engine or power cables, mistaking it for food. Shriekers also drag their tongues along the ground, searching for any colder edible material by taste alone.

Each shrieker is born with at least one live fetus growing inside of it. Once an individual consumes enough food, it will vomit up this fetus, now fully developed. The newborn creature begins to grow and hunt from birth; once it eats enough, it too will release its' offspring. This allows any shrieker pack to grow exponentially, potentially creating a massive threat. Once a shrieker lives for 24 hours, it will begin to molt, eventually becoming an Ass-Blaster, the final stage in the life cycle.


  • Pedro
  • Julio
  • Agent Rusk
  • Agent Statler
  • Dr. Merliss

See Also