It began with a year-long saga into the Watcher of Earth-1, the Monitor (he had to be color-corrected before you could use him, I think) peering into the lives of the DC heroes and villains, past and present, on Earths-1, 2, 3, X, 5, 6, S, Q, C, C-Minus, Earth-Haney, Earth-162 (home of Superman-Red/Superman-Blue), Earth-12 (home of the Inferior Five), Earth-28 (home of Dean Martin, Jerry Lewis, and Bob Hope), and Earth-616, (home of the...hey, wait a minute!):
Panels from DC Comics Presents #78 (February 1985); script by Marv Wolfman, pencils by Curt Swan, inks by Dave Hunt, colors by Gene D'Angelo, letters by Ben Oda
We got a sneak peak in the promo giveaway DC Sampler #3a whole magazine fulla house ads! The title hadn't been quite firmed up yet, however:
(Click picture to multiverse-size)
The second page of this double-spread ad showed up in regular DC comics, whetting our appetite and raising our hopes in the bleak despair of the post-Secret Wars era:
House ad for DC Universe: Crisis on Infinite Earths printed in World's Finest Comics #313 (March 1985)
But the following month, we got our biggest peep yet at DC's biggest event yet, now with new-and-improved title and logo! Can you count all the Earths? Of course not...they're infinite.
House ad for Crisis on Infinite Earths #1 (April 1985), printed in World's Finest Comics #314 (April 1985), pencils and inks by George Pérez, colors by Anthony Tollin, letters by Gaspar Saladino
There wasn't a whole slew of monthly ads to encourage you to read Crisisheck, the comic books themselves, with their red-sky tie-ins, were all pretty much full house ads for CoIE. A half-page ad pops up a few months later to remind you that your favorite DC character is in this series (unless your favorite is Nutsy Squirrel, who died tragically behind the scenes saving some chipmunk youngsters from an avalanche of antimatter nuts.).
House ad for Crisis on Infinite Earths #4 (April 1985), printed in DC Comics Presents #83 (July 1985), pencils and inks by George Pérez, colors by Anthony Tollin, letters by Gaspar Saladino
Then, everybody cried.
House ad for Crisis on Infinite Earths #7 (October 1985), printed in World's Finest Comics #319 (September 1985), pencils and inks by George Pérez, colors by Tom Ziuko, letters by Gaspar Saladino
And then, the DC Universe was never the same again.
And, what the heck, I'm gonna just blame it for this too.