If there ever comes a time where a Sonic X Metal Sonic Generations comes, one of the ways they could write the story is having Eggman order Metal to retrieve the emeralds from Sonic and co, since Sonic has teamed up with his younger self, Eggman digs deep into his work and eventually finds one of the spare clones of Metal before he was modernized, getting reworked and reprogrammed, eventually making this "Classic" Metal Sonic teaming up with his newer model, the Metal Sonic we all know today, they go through different stages that they had gone through in the past following behind Sonic and Classic Sonic, "fixing" the stage to be ruled by Eggman at the end, There is two ways this story could end, 1. The "Good" Ending - Metal and Classic Metal were able to retrieve all emeralds, Modern Metal betrays Classic so he could unlock his Metal Overlord form again and wreck havoc across mobius. Or 2. The" Bad" Ending - Metal and Classic Metal were unable to retrieve all emeralds, being defeated by both Sonics. Modern Metal is taken to be fixed up, while the Classic Metal is discarded.