Crisis on Every Earth
Seriously, though, if you look at DC history, they really can't go five minutes without a Crisis. We had:
- Crisis on Multiple Earths: A regular, recurring cross-over event between Earth 1 and Earth 2.
- Crisis on Infinite Earths: Where-in DC decided to get rid of the multiverse. Earth 2 is merged into Earth 1 as the "past" for the main continuity. Earth 1 is renamed New Earth.
- Zero Hour: Crisis in Time: In an attempt to clean up the continuity that was not entirely improved by CoIE, Zero Hero merged all the future histories of the DC universe. In the process, they also rebooted several characters, including Hawkman (who had the most hilariously awful continuity after CoIE -- was he an Egyptologist or a Space Cop or both? -- and yet, even after this, Hawkman was still a completely indecipherable mess of continuities).
- Identity Crisis: Where-in DC tried to make all their superheroes more "dark" and "edgy" which really just lead to them being mean and a little rapey.
- Infinite Crisis: Where-in DC was all "oh hey, that whole multiverse thing was a good idea after all. Let's have that, and we'll make it by having an alternate version of Superboy punch the very walls of reality". This is not a joke.
- Final Crisis: Where-in DC is just like "fuck it, let's have a big crossover event and call it a Crisis cause who really gives a fuck anyway?" There is no guarantee that this will really be the "final" crisis, although it's doubtful knowing DC.
Meanwhile, DC had a ton of other crossover events, some of which actually rebooted parts of continuity, such as Blackest Night, which eliminated the revolving door of death (well, it did for like three years or so), and Flashpoint, which completely rebooted DC continuity again (but it came after Final Crisis, so they didn't have to give it a "Crisis" name because that was the final one, obviously.
And yet somehow, after all of this, I'm still a fan of DC. I must love punishment.