I must clarify that I’m not much of a Pokémon fan. I watched it for a short time during my childhood, but soon switched to Digimon.
I started to draw realistic version of some of this beasties ‘cause I thought of it as a nice exercise on creature design.

This particular beastie was a bit more a work of character design. With most of the Pokémon I just decided to interpret the drawing mostly because any information about the creature was useless ramble about their powers. I can feel myself free to write their biological background because they have no story written.
This one had a story; a whole film was devoted to it, apparently. So I went along with it.

Mewtwo is the result of a so so cloning project of the creature Mew. He’s the single survivor of great number of clones (This reminds me alien resurrection). The accelerated in-vitro growth led to several unusual physical characteristics. For example the unhealthy pale skin. The most dramatic are the result of the plastic “umbilical cords” plugged to the specimen since it was a fetus. The perforations generated a sever disturbance in bone and soft tissue development, leading to the formation of deep cavities surrounded by swollen flesh in the thorax and abdomen.

It looks like a creature that skipped all faces between the embryo stage and old hood. This is pretty much what happened.

Thanks to the genetic material that gave live to it, Mewtwo has an insanely highly developed neural system. Due to the imperfection of the cloning process, a series of irregularities and deformities appeared in it.
The spine bifurcates at the dorsal region. The portion that is unattached to the body lacks of any support function, it’s purely neural. The creature also has two lumps that are concentrations of brain cells (protobrains); one at the point of the tail and another close to the head.

The hornlike structures on top of its head are actually developed sensitive organ, similar to antennae. The rounded tips of both hands and feet have similar properties.

The combination of all this features make this a incredibly powerful being capable of telepathy, telekinesis, elevating, controlling energy and electricity, etc.

He’s physically very weak and vulnerable. The strength of the psychic powers makes unnecessary the development of muscle. To this atrophy also contributes the fact that the thing was bred in a tube.
The jaw is rather reduced in size and has several little teeth.

The paper texture of the background, border and the stain brushes are thanks to: *struckdumb
I used the as well =yumedust ’s brushes.
[link]

Inspiration came from Carlos Huante and Alien Resurrection, moslty.

EDIT:
Thanks a million Da for the DD! And to ^rydi1689 for featuring it.
Thank you all for giving a look to my work. And for all your comments and fvs. They mean a world to me! If I could I would thank every one of you personally. ;)