There are several obviously Nobody oriented beings that appear seldom. The Time Bomb is one of these. The other two shown in the picture are known as Knight Head and Speeder. All three, and several alterantely-colored versions, appear on Gummi Routes.
Little is known about these small, unnamed Nobodies. They tend to appear and disappear quickly. It seems to be their main goal in life to prevent enemies from attacking important human-forms. They all appeared to defend Xemnas during his final battle.