Worlds will live. Worlds will die. If you're a completist, you'll spend a lot of money buying titles that you normally wouldn't, looking back on your collection a decade later, wondering why exactly you have that Losers Special or perhaps that Manhunter #0.

The promises sound familiar, and DC both pioneered and mastered the event that would shatter your senses and realign your reality. Infinite Crisis is just the latest, and only a fool would consider it the last.

As most probably know, Infinite Crisis serves as sequel to that original, Marv Wolfman and George Perez' Crisis on Infinite Earths, the first crossover to address continuity. DC had been publishing for fifty years by 1985, and in that fifty years, the company had built up a glorious heaping mess of storylines both stupid and brilliant. What worlds they hadn't created to explain the absence of heroes for some time, they bought.

The Freedom Fighters, killed in the pages of Infinite Crisis #1, came from Earth-X - characters originally published by Quality Comics. On Earth-S, the heroes from Fawcett Comics such as the Marvel Family and the way underused Spy Smasher, Bulletman and Mr. Scarlet resided. Just before Crisis on Infinite Earths, then-publisher Dick Giordano snagged the rights to the Charlton Action Heroes such as Blue Beetle and Captain Atom.

(DC didn't even try to add in the Archie Comics heroes when they briefly had the rights. They just started a whole new and short-lived imprint, Impact! Comics.) Many Earths merged into one. Yet the continuity got sticky again after twenty years, with characters never adequately explained and editorial demands making the question of who met who when and why even more confusing than before. Hence Infinite Crisis. And yet…this marks the FOURTH crossover to redefine continuity.

The forgotten events, the ones that Infinite Crisis has not yet referenced, but knowing Geoff Johns it probably will, are Zero Hour: Crisis in Time and The Kingdom. Zero Hour itself took its cue from Armageddon 2001, a summer crossover event published in 1991. There Matthew Ryder, the denizen of a future dystopia started in 2001 (gasp)*, had dim memories of having been saved as a child by a superhero, but he could not remember which one. In the years since, the superheroes had been systematically wiped out by an armored despot named Monarch, who had once been one of their own.

Using an experimental time travel device, Matthew Ryder went back to 1991 to try and find out who Monarch had been before, and hopefully put a stop to his evil plans. The trip through time transformed the young engineer into the yellow and black chronal warrior called Waverider (visually striking enough to show up on Justice League Unlimited).

Waverider could see into heroes' futures when he touched them. No, those futures didn't include long walks holding hands with Waverider. Improbably, it turned out that Hawk (of "…and Dove") would become Monarch, and the quantum-powered Captain Atom would knock him into the timestream.

At the end of Armageddon 2001, Waverider discovered that he was the hero that had saved himself as a young boy, and, in a future with no Monarch, that boy would grow up and become one of The Linear Men, guardians of the timestream. They inducted Waverider as one of their agents, sworn to protect the one true continuity even though Waverider himself violated it, which made things awkward at the Linear Men company picnic.

The real end result of Armageddon 2001, though unintended at the time, was Zero Hour.**

Monarch got a taste for chronal energy, and his constant sucking on the time pipe transformed him into the even more powerful villain Extant. Wishing to remake reality in his own image, Extant figured that he could just cause a universal do-over, with him in charge.

Unfortunately for Extant, another hero-turned-villain already had more power and stole his thunder. Fresh from destroying Oa, everybody's favorite Green Lantern turned genocidal maniac Parallax, Hal Jordan, elbowed Extant aside as DC editors reached in and tweaked a few things about their characters' pasts.

Everyone seemed to forget that Lex Luthor had once been a fat older businessman before cloning himself into the handsome rogue we know today. Batman never found out who killed his parents (though, just as in Batman Begins, Joe Chill murdered them). Jerry Lewis had never made The Day The Clown Cried.

Next: Kingdom Come, DC One Million, The Kingdom and just what is Hypertime?

*originally the text read unclearly "future dystopia of 2001;" Matthew Ryder actually began his narrative from much later -- Monarch established his rule in 2001. Thanks to critics from the Millarworld forum for pointing that out.

**The sentence originally read "Therein lies Zero Hour." Niftier phrasing, perhaps, but not quite making explicit the point that without Armageddon 2001, we wouldn't have had the initial villain of Zero Hour. Again, thanks to the aforementioned critics for pointing this out.

Derek McCaw