What, again with the Mego stuff? Well, yeah.
It's legendary in toy collecting circles how Mego had been first approached by Lucas (or an associate) about licensing this movie coming out called "Star Wars" (yeah, you may have heard about it), but Mego decided they weren't interested, so Lucas went to Kenner, who bit on it, and the rest is history.
You may even be aware that the death knell of the original 12" GI Joe line was due to the rising cost of plastics in the 1970s (the line was transformed to "Super Joe" for a short time, kind of a bendy Joe line), and this was why Kenner made their initial Star Wars line in the smaller scale.
Mego was also hit by the rise in plastics, and they made their own try with a smaller action figure line:... Comic Action Heroes! They later had their Pocket Heroes line, but we'll get to that another day.
Superman wasn't joined by Supergirl or Mr. Mxyzptlk in this line... and no, I have no idea why his insignia was so shiny, either! The line's main focus seemed to be on the "action" part of the name, as there were playsets produced that came with a hand-operated air pump. When you squeezed the pump, something happened... as you can see from the Fortress of Solitude playset:
I find it odd that this came with a Superman figure, because I'm sure a lot of parents ended up buying their child a Superman Comic Action Hero and a Fortress, and their kid ended up with two Supermen! I also find it odd that the Fortress of Solitude came with a meeting table. It seems it was really a Hall of Justice!
The line had one spin-off... the ultra-rare Comic Action Heroes boardgame, which I've only seen offered on eBay once!