Maybe Marvel is trying to do something about climate change.

That's one possible explanation for why the publisher is recycling the titles of half a dozen, and probably more, of its events from over the years. In the past week, Marvel has announced events titled Planet Hulk and Armor Wars, and before that we found out about Civil War, Age of Ultron vs. Marvel Zombies, Secret Wars, and the slightly retitled Years of Future Past.

These have all been presented as teasers with artwork but little other context. In some cases, the illustrations look like the stories are clearly connected to their namesakes (Armor Wars, Civil War), and in others they look like new stories using old names (Planet Hulk, Years of Future Past).

There's a clear business reason for all this. Name recognition is some of the most valuable currency in the media right now, and there are seemingly guaranteed sales that would come with naming a new comic something that people remember.

But what about the story reason, if there is one? Some observers have guessed that these series will amount to little more than single-issue What If?-style stories, but over at The Spire, Steve Morris has a different explanation:

Jonathan Hickman and Esad Ribic’s Secret Wars seems to be the catalyst to all this. Hickman’s writing has introduced the concept of ‘incursions’ to the Marvel Universe – sort of black holes which drag alternate worlds close to one another, I think. As you can see in the image above, the storyline seems to be merging a whole load of different characters into the same world – lots of alternate universe stuff going on.

Now, as far as I know, Civil War, Armor Wars and Planet Hulk all took place in the same Marvel Universe. Days of Future Past, Marvel Zombies and Age of Ultron certainly verged into alternate universe territory, though.

Maybe the implication here is that there are universes where Civil War, Planet Hulk and Armor Wars had different outcomes. Imagine a universe where Civil War went on forever. Chilling.

We'll all find out soon enough, surely, but I for one hope we haven't reached the end of the Marvel recycling announcements. They haven't released any teasers for a Maximum Security series in 2015, after all.