Ground-types and dark-types have always been pretty unique. While ground-types are normally based off from the habits of actual animals, dark-types are known for being based more off from myths and old wise tales. The Sandile evolutionary line could pass off as being a little bit of both.
Sandile is a mixture between a sandy colored crocodile and black stripes that are similar to the old stripped uniforms prisoners used to wear in jails. The black skin surrounding its eyes is similar to a mask, which is similar to a burglar’s mask (which may be why it’s also part dark-type). Sandile and its evolutionary relatives are the only Pokemon to have their unique type combination. According to its pokedex entries, Sandile live buried in the sands of the desert. The sun-warmed sands prevent their body heat from dropping. It apparently moves along below the sand’s surface, except for its nose and eyes. The dark membrane surround its eyes protect their eyes from the sun. Considering its habits, Sandile may also be based off from a “sandfish”, a desert reptile that is able to move through the sand as if it were swimming. Sandile’s name seems to come from the words ‘sand’, ‘crocodile’, and is possibly meant to be a play on the word ‘sandal’.
Once Sandile reaches level 29, it evolves into Krokorok. Krokorok is a bit taller than Sandile and gets about on its hind legs rather than on all fours. Like its pre-evolution, it is stripped black and tan, though also has a spiked back and tail leading from its neck. Its stomach is pink and stripped. Like Sandile, Krokorok has the same black ‘mask’ covering its eyes. Its pokedex entries state that Krokorok live in groups with a few individuals. Protective membranes shield their eyes from sandstorms. The special membrane covering its eyes can sense the heat of objects, so it can see its surroundings, even in darkness. Krokorok appears to be based off from a narrow nosed crocodile and possibly a caiman. Its posture is like a criminal’s, which may be a reference to its type. Krokorok’s name most-likely comes from the words ‘crocodile’ and ‘rock’.
Finally, once Krokorok reaches level 40 it evolves into Krookodile. Krookodile is large and red and black stripped, the black stripes appearing like claw marks. Its feet are ringed in black, almost as if they were shackled. It has black spikes on its back and has the same black ‘mask’ as its evolutionary relatives. According to its pokedex entries, Krookodile never allow their prey to escape. Their jaws are so powerful; they can crash crush the body of an automobile. It can expand the focus of its eyes, enabling it to see objects in the far distance as if it were using binoculars. Its name is probably a combination of the words ‘crook’ and ‘crocodile’.