The Avengers: Earth's Mightiest Heroes, on Disney XD
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Well, before the series actually started, there was a microseries (20 minisodes roughly 5 to 6 minutes each) that I never got around to watching when they were first released. But I did finally watch them online when I started this review of the series (after having seen the first few regular episodes).
As you can tell from the microseries, there are a lot of disparate elements that are all ultimately connected. I quite like how much thought has apparently been put into all of this. Anyway, in the two-part series premiere, 74 of the world's most dangerous supervillains escape from SHIELD's four prisons (the Vault, the Cube, the Big House, and the Raft), which had been predicted by one of the prisoners, Mad Thinker, during the microseries. The first villain to make trouble is Graviton, and Nick Fury tries to fight him, but so do several heroes: Iron Man, Thor, Wasp, Giant-Man, and Hulk. After they take down Graviton, Iron Man gets the other heroes to join him in a new team called the Avengers, though they don't exactly get along that well. Hulk leaves pretty soon, because of his own problems, but while they're searching for him, they discover Captain America, frozen in ice since the 1940s, and he joins the team, too. A bit later, the team helps T'Challa (the new Black Panther) defeat Man Ape and reclaim his throne in Wakanda, but he then sets up a council to rule his country, while he joins the Avengers. Of course, the team is going to need all the help it can get, because there are still 73 escaped supervillains to be recaptured. Plus various organizations to fight, like HYDRA and AIM (Advanced Idea Mechanics), and any number of other enemies, including rogue Asgardians the Enchantress and the Executioner.
There's not much else I can say yet, but it seems reasonably well written, I like the animation well enough, and it should be fun trying to get to know all the characters (heroes and villains alike), and trying to make sense of all the different pieces of the story. ...And, um... looking at this review in 2019, I can't even remember if I saw all of season one, but I definitely didn't see season two, because I had lost access to Disney XD by the time it aired.