The following list is full of enemies that have appeared in the Sonic Universe of video games, that also make an appearance in Mushroom Kingdom Fusion. These enemies appear in Mobius, but may also recur in the other worlds, hence the fusion.
Enemies of the Sonic Universe
A robotic life form modeled after the Chao's guardian, Chaos. It was a expriment made by Dr. Eggman's grandfather Gerald Robotnik and is used by GUN. It's a liquid creature that can attack with lasers, extending tentacles or splitting into multiple miniature blobs. Its only weakspot is the robotic head holding the liquid body together. Unlike most robots found in the Sonic games, it has a energy core instead of an animal inside it.
These creatures are bee-like robots that were created by Dr. Robotnik. They are among the first enemies that Sonic fought in the Green Hill Zone in his original game. They fly through the air, only stopping in order to fire lasers at their enemies. This concept of flying bee robots has since been reused, usually only varying in paint job.
The Chopper is a piranha-like robot powered by a trapped animal piloting the robot. This guy was one of the very first Badniks ever, which would appear first in the Green Hill Zone, and later in the Bridge Zone. It jumped through bridges in order to bite Sonic.
The Cluckoid is another Badnik showing Dr. Robotnik's strange fascination with chicken like robots. The Cluckoids were originally stationed on the Floating Island, in the Mushroom Hill Zone. The Cluckoids were able to inhale large quantities of air, and exhale it, in order to hinder the progress of Sonic. The Cluckoids are stationary, and resemble weather vanes.
Another of Dr. Robotnik's first Badniks, this robotic crab resides in Green Hill Zone. It doesn't do much aside from trying to walk into you, taking a short pause to shoot a couple of energy balls from it's claws. Some claim that Crabmeat are notorious tricksters, but this is both unconfirmed and unbelieved. Much like the others, it is powered by a probably uncomfortable animal.
A basic troop in the Eggman Army in the 3D games. Humanoid with an Eggman shape to them, they are basic combat and labor drones. Variations include armed ones called Gun Pawns and Shield Pawns with shields of varying strengths.
A mole-type robot, the Mad Moles hid underneath the Mushroom Hill Zone in small hatches. They wielded large mushrooms that they threw. When hit, Sonic was knocked back with stunning force. Interestingly, the Flying Battery Zone was piloted by a repainted Mad Mole.
Another example of an early Badnik, this is a robotic Hermit Crab created by Dr. Robotnik, and powered by small animals. Eggman seemed to have wised up to his enemies' tactics, as this model has spikes that prevent jumping on it- it can only be damaged from the front. "Yadorin" is Japanese for Hermit Crab, from whence this beast gets its name.