For a company that prided itself on their role in the fight for the creators' rights, the 90-ies Image made a lot of steps that infuriated the audience and destabilized the industry. Yet, the energy involved with seeing superstar artists achieve huge success under their own names also lead to tweaking of the standard superhero formula.
The inter title crossovers, designed as disposable marketing ploys started getting more traction in the industry as the idea of a shared superhero universe settled into its own tempo. Even if the disparate characters rarely formed a more complex relationship beyond the mutual respect they gained after the initial fight brought on (from the story point) by their differences, the same largely wasn't true for the crossovers between Marvel and DC. For obvious reasons, the story elements could not be carried over into the individual titles, nor did Superman meeting Spider-man impact the characterization of either of the company's flagship characters.
Truthfully, the publishing model both the superhero giants use routinely necessitates that a lot of their own material is likewise disposable. Since Marvel rejuvenated the industry in the 1960s, the idea of subplots and controlled story evolution added some color to the genre's previous typical stand alone adventure stories. Seeing Power Man and Iron Fist team up in their own title seems much less abrupt once the editorial establishes a feeling of characters overlapping and communicating with one another.
Even if the fans was keenly aware of the marketing ploy, they didn't seem to mind it, as long as they were getting more diversified entertainment for their money. The inter company crossovers have become increasingly rare in the current market, with JLA/Avengers being the last one produced and sold as an event in its own right. Interestingly, the series' writer, Kurt Busiek, followed up on the events of the crossover in his subsequent JLA run. The move was not unprecedented, yet it bears to mind many of the colorful ways in which Image played with the same idea.
Perhaps the most famous example hails from "Batman/Spawn", the Frank Miller written crossover that posited that it featured the version of Batman featured in the writer's seminal "the Dark Knight Returns" mini-series. The project was long time in making and ultimately led to Spawn creator writer/artist Todd McFarlane stepping back from the art duties, and remaining in more of an editorial capacity. The story was formulaic and easily forgettable, going so far to achieve a notoriety for its over the top qualities. Still, a particular moment was deemed significant enough to carry over into the main "Spawn" title.
A Batarang thrown at Spawn in one of Batman's tantrums lead to a temporary injury to the undead Image superhero. In fact, the chronologically next "Spawn" story had his face in the stitches, with the anti-hero going so far to make a veiled reference to his attacker.
Interestingly, Batman himself had a far larger role in another of the Image titles, appearing as he did in a crossover with "Darkness", during the Scott Lobdell run on the Top Cow title. Following the Garth Ennis' co-written introductory arc on the title, Lobdell seemed determined to remake the Jackie into a more familiar superhero vigilante character, and ironically Batman was key in that. The change of heart in the mobster came directly because of his meeting DC's best selling character, setting off a subplot that would define the rest of the writer's run.
Thematically, the arc had Jackie (defined by Garth Ennis as cheerfully immature Italian stereotype) break away from his mafioso uncle Frankie, previously portrayed as a parent figure. In the process Lobdell remade the senior gangster with a heart of gold into a much more brutal figure, leading the succeeding writer to rectify the mistake in his follow-up run. The introduction of uncle Pauly seemed a thin veiled attempt not to directly step over the continuity, while returning the book to the superhero stories grounded in the mafia milieu.
With the end of Batman's influence over Jackie also ended the strange references to the DC hero whose moralizing lead to Jackie entering the witness protection program and giving up his mob allies to the police.
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