I had this dude. He was always a favorite because he was so fantastically heavy, well-jointed, and easy to plant—you could shoot missiles and Shogun Warrior fists at him and he was like, “That’s all you got? I’m still standing.” I had this sky sled, too.
Like the Micronauts, the Metal Men had no back story. They just appeared from outer space, ready to party in whatever world you made for them. Check out the ’78 Metal Men catalog at Plaid Stallions. There’s also a nice entry at BugEyedMonster.