<p>Not counting Thanos, who stayed hidden in the shadows behind Loki with The Other serving as his mouthpiece, there were six main villains in Phase 1: Obadiah Stane, the Abomination, Ivan Vanko, Justin Hammer, Loki, and Red Skull. Of those, half of them died.
</p><p>Phase 2 killed all its main villains (not counting Loki and Thanos who weren't directly the main villains of Phase 2 films): Aldrich Killian, Malekith, Alexander Pierce, Ronan the Accuser, Ultron, and Darren Cross.
</p><p>Now, for Phase 3. Helmut Zemo certainly survived, Kaecilius is a little more ambiguous but is widely believed to be turned into a Mindless One, plus the whole mention of "eternal life" (though the exact nature of this isn't revealed), so his survival is a more popular interpretation.
</p><p>Is this a trend in Phase 3? I guess we'll find out in Guardians of the Galaxy 2, Spiderman Homecoming, Thor Ragnarok, and Black Panther. Of course, as I said before, even if Thanos loses he's most certainly going to survive, unless they go back to their old style in Phase 4 and have Thanos encounter Dormammu somehow
</p><p>I'm not gonna say my opinion on the types of villain defeat again because I often feel insecure about having unpopular opinions (and even the pony fandom gave me a hard time for them) but if this is a conscious decision on their part I think I can guess why - because today fans find the villain deaths to be too cliche and overused. Lately this is the only series where people have been satisfied with the films (or episodes in the case of TV series) that did this, aside from the obvious Joffrey and Ramsay in Game of Thrones. Disney movies and Supernatural are doing this too following the deaths of King Candy in Wreck-It Ralph and Abaddon in Season 9, respectively.
</p><p>But, as Kaecilius is still ambiguous we can't be 100% sure yet.
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