So apparently, circa 1986, there was a cartoon series called Defenders of the Earth. It lasted 65 episodes, though I don't think I ever saw it when I was a kid. The idea was that the heroes of three King Features comic strips, Mandrake the Magician, the Phantom, and Flash Gordon, would team up to defend the planet against the evil Ming the Merciless. Along with the cartoon and a toy line, Marvel Comics' Star imprint launched an on-going series that only lasted four issues.
In Issue # 1, written by Stan the Man (with an "assist" from Bob Harras), we get a team origin. Flash Gordon's spaceship crashes on Earth and is found by Mandrake and Lothar. After escaping from robots sent by Ming the Merciless, Flash warns his rescuers that Ming plans to invade Earth and that his wife and son have been captured. The heroes decide they need help, and travel to the jungle to recruit . . . The Phantom! The four fly a spaceship to Mongo and into a space battle, but Mandrake uses his illusions to trick Ming's fleet into attacking his own palace! Ming flees to a new base on Earth (in the Arctic), but the heroes find that Flash's wife, Dale, is dead (although her soul is trapped in a crystal shard). There's a lot of kid sidekicks in this issue, but fortunately they're mostly sidelined. And I still have no idea who Lothar is or what contribution he makes. . . [Edit: Later research reveals he is Mandrake's assistant, is super strong, and, his toy packaging describes him as a "magic ninja of the Carribean". That's awesome.]
At the beginning of Issue # 2, Flash's wife, Rick, has the bright idea of putting his mum's soul into a computer and naming it "Dynak X." I wish more people would think of that! The heroes discuss getting a new HQ (instead of just crashing in Mandrake's mansion), and some allied aliens called the Cryl agree to build a new base dubbed "Monitor." I'm guessing this is all effectively a prequel to the cartoon, but I still have no idea since I've never watched it. Anyway, Ming mercilessly intercepts the group's communications and launches an attack on the Cryl spaceship, but Flash and Mandrake save the day. Ming then attacks Monitor, but the Defenders of the Universe set off an explosion to trick Ming into thinking they're all dead. I make jokes, but it's not bad for what it is.
I've had Issue # 3 for years and must have purchased it right off the rack. "It's a rumble in the Jungle! Brothers vs. Brother" promises the cover, and indeed the story does involve The Phantom going up against his brother, Kurt Walker, to protect the indigenous Bandar people (the people with whom The Phantom usually lives with). Walker is torqued that he got passed over to be The Phantom, but while trying to steal some jewels from the Bandar he sneaks into an old cave, finds a skeleton wearing a strange costume, and dons it to become the demonic N'Dama! N'Dama takes over the Bandar village until The Phantom arrives to save the day. N'Dama ends up seemingly consumed by his own power. This was effectively a Phantom solo story, but good quality. If it had been a solo Avengers story, I wouldn't have blinked.
If the previous issue focused on The Phantom, Issue # 4 is all about Mandrake. Earth's mightiest magician recalls how he found the orphaned boy Kshin, and decides it's now time to initiate the lad in the ways of magic. He starts by sharing his own origin (family killed by avalanche, saved by monks, excelled in mystical arts, etc.) and then leads Kshin in meditation. But meanwhile, Mandrake's arch-rival, Dr. Dark, escapes from another dimension (with Ming's aid: super-villain team-up!) and invades the mansion. Lothar is quickly stunned, and we're treated to a Mandrake vs. Dr. Dark magic duel, which appears on the page in very much a Doctor Strange-style. Dr. Dark casts a cool spell to tie Mandrake's life force to the flickering flames of a candle, but Mandrake helps Kshin cast a spell to free him. And then, a cliffhanger: the Defenders of the Earth discover Ming's plot to rule the word with ice men! Alas, since it's the final issue, we may never know who prevailed . . .
Overall, these are perfectly serviceable comics, especially for their intended age bracket. They don't exactly leave me breathless for more, but I know I've read far worse!