Neptoids: The Neptoids seen on Earth are part of an advance scout party sent by alien invaders intent on taking over our world. The Neptoids are not actually from the planet Neptune, but maintain a base there to better strike at Earth. The similar name, they insist, is purely a result of our poor Earthling comprehension of their language.
The Neptoids have run afoul of Captain Satellite and the other heroes of Earth on more than one occasion. During the first such encounter, Cap and Shelly Ericson realized they were in love while they were held captive aboard a Neptoid flying saucer. No word on the Neptoids' opinion of the relationship, but the adventure didn't work out for extraterrestrial interlopers that day.
The Neptoids are dogged in their determination to conquer our globe, or at least set the stage for such a conquest. To fail would mean returning home having accomplished nothing. That probably wouldn't go well.
Phantom Rogue: The Phantom Rogue isn't in the super villain game for the power, and he isn't in it for the thrills. He's in it for the money. Cold, hard cash, please. True, he took control of a splinter faction of Third World once, but that was just the means to an end. He's after riches, pure and simple.
The Phantom Rogue has no special powers or gimmicks, though he sometimes leads people to believe that he does. No, his primary abilities are incredible greed, astonishing sneakiness, and an improbable ability to escape from danger at every turn. It's assumed that he adopted his ghost trappings to reflect his elusiveness.
The Phantom Rogue's true identity is unknown. He has impersonated assorted people, both real and of his own invention. Among his best-known capers are the time he stole Miles Major Memorial Stadium using a dirigible and holding the United States for ransom with the Stupendo Death Ray. He has run afoul of Captain Satellite several times, but always manages to find some means of escape.
Psychedelic Man: Dr. Clive Frye was considered a maverick among his fellow scientists at an obscure west coast facility. He had become obsessed with the wild idea of tapping into alien dimensions in the search for alternative fuel sources. The other researchers warned Frye of the dangers of tampering in areas he didn't fully comprehend, but he refused to be deterred.
It all went horribly wrong one day, and Dr. Clive Frye paid a terrible price for his hubris. What precisely happened - what Dr. Frye saw and experienced - remains unknown to this day. The result, however, was that “Clive Frye” effectively ceased to exist. In his place was a being that called itself “The Psychedelic Man.”
The Psychedelic Man is not human, but rather a type of organic color. His “body” is actually a largely translucent shell that contains his true form - a kaleidoscope of swirling and changing colors. He can alter his physical form according to his whims, and has displayed the ability to stretch and even split off body parts.
Clive Frye's mind was twisted by the process that transmuted him into the Psychedelic Man, and his chief goal now is destruction. He has clashed with the duo of Captain Satellite and Shelly Ericson, and with the Invincible Alliance. Though defeated and seemingly destroyed on more than one occasion, the Psychedelic Man always returns.
Sultura: She's bad. She's ambiguously European. She's famous for being infamous. She's Sultura, and she's a constant thorn in the side of those who fight for justice.
Sultura is a safecracker, thief, kidnapper, counterfeiter - the list is seemingly endless. The most consistent trait in her career is her vanity. Her motto “I make being bad look damn good!” is not just a catchphrase, but her goal in life. Most people would not go so far as to print up fake money with their own picture on it, but most people aren't Sultura. She may end up redefining narcissism, if anyone ever discovers what the limit of hers actually is.
Sultura has particularly earned the wrath of Shelly Ericson for taunting her as Captain Satellite's “concubine” during one brazen heist. Shelly has promised that there will be payback each and every time she gets her hands on the femme fatale. And Shelly isn't the sort to make such a promise and not fulfill it.