First Appearance: Nova #8 (2008)
Abilities: Cosmo is incredibly skilled at all security protocols and has telepathic (how he communicates with other beings) and telekinetic powers.
Chances he's in the movie: 50% (but should be 99%)
Lowdown: Little is known precisely about Cosmo's background except that he was an animal used for space travel experiments by the Soviet government in the 1960's. Something happened during his flight and he eventually found himself at the interstellar space station Knowhere.  At some point he was mutated to increase his intelligence and lifespan. When the Guardians of the Galaxy decided to use Knowhere as a base of operations, Cosmo became an ally and worked with them during a number of missions.  He'd be a fan favorite, but Marvel may decide with Rocket Raccoon and Groot they can do without a telepathic dog in their "Guardians" movie.  Cosmo may also just be too similar to those talking dogs from Pixar's "Up" for comfort (although he's a lot smarter).