Going Back to Mars
MM appeared in GLC #4, and then mindwiped everyone there (I think it was just Guy...) and left. He also appeared at the end of Legion Lost #5. Not sure if related to the obvious nod to the status of the Martian race in OP's post, but worth mentioning, at the very least. I think he's looking for something? A War of the Worlds-style story arc focused on MM could be pretty cool, imo.
And Stormwatch #5 had a lot of references to stuff that'll happen in the future. I made a thread about one panel in particular here.
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