Grounder is a fictional robot in the Sonic the Hedgehog universe, based on the Badnik of the same name from Sonic the Hedgehog 2. He is a loyal, yet dim-witted robot who serves Dr. Robotnik who first created his "brother" Scratch and was cloned with part of a tail feather. However, because Scratch pulled a lever on the machine that wasn't supposed to be pulled, he came out entirely different to Scratch.
Grounder is a short, green robot with continuous tracks for mobility. He has a drill for a nose as well as two on the ends of his arms. Grounder specializes mainly in gadgetry; he can turn his drill "hands" into any number of weapons or tools, stores assorted equipment (commonly, a telephone) in his torso, and (according to the episode showing his creation) even has the components of a Swiss Army knife installed in his tongue. Grounder also seems to be the most fragile of Robotnik's robots (himself, Scratch, and Coconuts), getting blown to bits slightly more often than the others.
Mean Bean Machine
Grounder appears as the eight opponent in the puzzle game Dr. Robotnik's Mean Bean Machine. He is the last opponent one could consider easy. However, he still isn't a pushover either. He is the margin point where the game becomes much more difficult.