The robot stands 1.75" high. The eyes were made by blending different colors of Dots together. His internal structure is trimmed toothpicks, and he's got some detail carving on his face and body, which didn't show up due to photo resolution.
Except for the ones in the last photo, all of the Martians were made by reshaping the Dots by rolling, flattening, trimming, etc. Facial features were made by trimming additional piece; when you cut into the candies, they're naturally sticky, and adhere to other pieces very well, so these are all completely edible except for the toothpick portion.
The plateful of Martian heads are made from Spearmint leaf candies, turned upside-down and featuring dark-chocolate-piped eyes. They'd be fun cupcake toppers, etc.
The little red guy is so cute, I dream of someday creating an entire army of candy robots...