Pickle Rick is a version of Rick (C-137) first seen in the Season 3 teaser of Rick and Morty. His only functional body parts are his eyes and a mouth. This situation forces him to create gruesome means of transportation.
Only two augmentations were shown in the teaser, but Dan Harmon and Justin Roiland confirmed that this continues to progress to even more fantastic pickle forms.
Cockroach Pickle Rick
Rick is first seen wrapped up in cockroach limbs that twitch when Rick presses a nerve with his tongue.
Rat Pickle Rick
Constructed of rat limbs and brain, this form of Pickle Rick is very nimble and demonstrative a level of athleticism not often seen from Rick.