I have no connection to Micronauts, having been born in the late 70s I missed this whole amazing line even though I had two older brothers that did their part to introduce me to things like Star Wars, fart jokes and the ability to cut someone out of your family for good. Too dark? Okay let's get back to these crazy alien dudes.
These three Alien figures were released later in the Micronauts line, 1979, and became fan-favorites, usually showing up in collections such as ours that don't feature any other Micronauts action figures. From left to right in the photo above you have Membros (the orange gentlemen named so because of his massive brain that looks a bit like a decent 70s hairstyle), Repto (in the green with orange wings and probably named that because of his green skin), and finally Antron (in the purple with the four well-armed arms).
These figures are simply amazing and usually found very loose because of how much kids loved playing with them. Finding a mint, complete figure in good shape without loose limbs is not an easy task. We got these guys in the shop not too long ago and even though they're in great shape with good joints, our Membros suffered a broken cord that goes from his gun to his backpack which is pretty common due to the brittle plastic that was used on that cord.
We also have a variant of the Repto - one figure with an orange brain and another with a white.
These figures were released in the last year of G.I. Joe's original run, 1994. So these were most likely designed by an in-house designer around 1993 or so. I stand by my math above, with the thinking that whoever worked on these most likely was at least aware of the original Micronauts aliens and used them for inspiration. Some of the similarities are too much to ignore.
It's also nice that all of these figures have really really beautiful card art. Art on the older figures was always amazing and did most of the work of selling the toy that could barely live up to what the art was portraying.
Now I'm going to say that whoever is designing cheap figures for this line is probably not immersed in the toy world and most likely didn't draw inspiration from either the Micronauts or the G.I. Joe aliens, but that's pretty arrogant of me and may be completely false. Heck, this person may be a huge toy fan and may already know about the similarities between the two previous toyline aliens, whereas my theory about the Joe designer may be way off and that person may have never even laid eyes on the original Micronauts figures before putting pen to paper for designing the Lunartix aliens. Whatever the facts may be, all of these figures are now all best friends and plan on traveling the galaxies together (or sit on a shelf in our house).