Hailing from a time between the extinction of the dinosaurs and the life of mammals there were species who lived to correct the world in their own twisted ways, the first specimen, code named Shredder, was found dormant buried away in everest, but a large extinction event hasn't happened yet, and humanity brought them back. This is no regular animal, and the creatures meant to correct mass extinction, are now the ones causing it.
Code name Shredder, originally thought to be just a large, land baser predator, turned out to be a parasitic egg layer, starting with the disappearance of one scientist, it seems the subject is multiplying into multiple smaller versions of itself, no larger than a simple dog.