In Final Egg, two large stasis tubes can be found. One holds Metal Sonic, while the other holds an unknown Sonic-based robot, later referred to as Mecha Sonic Mark III by Ian Flynn. This robot has no importance in the story, however, it seems to be based heavily on the design of Mechagodzilla from the "Godzilla" franchise's Shōwa era, due to many similar parts and possible textures from the robot. This also seems to be a reference to Mecha Sonic Mark I, also known as Silver Sonic from Sonic the Hedgehog 2, whose concept art also shows similarities to Mechagodzilla.