A-Z Challenge word : "Carcenosaurus"
That's right, I actually managed to keep a drawing close to the original name this time! Dislike my result though.
Now for the mandatory ass-pull of a background!

The Carcenosaurus is something of an anomalous species. Each one was once a large reptilian of indefinite species, degenerated by a cancerous catalyst from a creatures bite. Over time, uncountered surface cell-growth and mutation alters their shape, deforming the victim until its original species can only be discerned through autopsy. Limbs fuse together and fracture into new branches of joints or are shed completely as the invasive psuedo-cancer invades deeper. The pattern of the changes often resulting in distinct final shapes. The two most common are one resembling a kind of land-bound cephalopod with tendril-like grasping mouthparts and greatly subdued ambulatory function, and the other form being centipede-like, with non-uniform bone structures forming its legs, and a mouth running almost the entire length of the central body.

Mature Carcenosaurus individuals are rare, as most juveniles die of natural causes in their incapacitated half-mutated states. Those that do survive long enough to endure the full change will find themselves returning to elevated mobility, and as an exclusive carnivore with an anaesthetic effect in their saliva to help subdue prey. Even in this completed state they are still far less agile than most other creatures, and rely on ambush to secure their food. Any creature that survives an attack after having been exposed to their saliva will typically succumb to infection and begin the process of mutation, though this is rare given how trap-like most Carcenosaur mouthparts tend to be. Mature adults have a long lifespan, but that varies greatly between individuals. Though they have great resistance to poisons, toxins, disease, and have no noticeable physical detriment in old age, they eventually perish due to the spontaneous and systematic failure of ALL their organs, the only warning of the strangely sudden end being a brief and furious attempt to attack anything and everything in the vicinity. Carcenosaur corpses that die of natural causes decay at an alarming rate, generating surprisingly little gas nor a particularly strong scent, and leaves the malformed skeletal structure completely intact and almost completely bleached white. It seems likely that they were engineered to act as a way to unbalance the ecology of certain planets or biospheres, probably as a weapon. Perhaps even as a way to cause a cascading natural extinction on profitable planets with problematic life.