There's no denying Disney's (NYSE:DIS) The Avengers was a massive success in 2012.
After all, with its box office debut last May, the film quickly set a new record for the largest-ever weekend opening by taking in more than $207 million.
Then, The Avengers proceeded to not only set a new high mark for the largest ever 10-day gross at more than $373 million, but it also became the fastest-ever movie to reach the $500 million mark after just 23 days.
In fact, when all was said and done after 22 weeks on the big screen, The Avengers stood third only to Avatar and Titanic in gross ticket sales after managing to pull in a total of more than $1.5 billion worldwide.
It should have come as no surprise, then, when Disney announced last month Robert Downey Jr. had agreed to portray Iron Man in at least two Avengers sequels going forward, with the next installment slated for a May 2015 release and titled Avengers: Age of Ultron.
Here's why The Avengers could fall
So far, anyway, it has seemed a foregone conclusion Marvel's The Avengers would ultimately reign supreme for an extended period of time atop its perch as the most successful superhero franchise of all time.
On Saturday, however, something happened to upset the generally accepted order of things.
Specifically, that's when DC Comics fans rejoiced after Man of Steel director Zach Snyder made a surprise appearance at this year's Comic-Con convention to announce that Batman will join Superman on the big screen in a Man of Steel sequel.
For any doubters out there, the plans were later confirmed by Time Warner's (NYSE:TWX.DL) Warner Brothers Studios, with the film's target release date set for sometime in -- you guessed it -- 2015.
Of course, some people might say Warner Brothers and DC Comics are crazy to release this sequel anywhere near the same time as Marvel's Avengers: Age of Ultron.
That said, however, this is also an unmistakably direct (and perfectly reasonable) shot by one of the world's most successful studios at curbing the growing box office supremacy of Disney's Marvel Entertainment.
Why DC's characters are a viable threat
Remember, in this case, we're talking about two well-loved superheroes who have already proved that they can be winners on the big screen.
Man of Steel, for example, has already won more than $635 million in global ticket sales in its first five and half weeks in theaters, and Warner Brothers' most recent three Batman movies -- Batman Begins, The Dark Knight, and The Dark Knight Rises -- took in a combined total of more than $2.46 billion by the end of their own theatrical runs.
What's more, as Marvel has already shown with The Avengers, movie-goer's wallets simply fly open when studios can find a way to effectively combine their superheroes' efforts into one ridiculously awesome production.
Now, this doesn't mean Dark Knight actor Christian Bale will reprise his role as everyone's favorite caped crusader next to Henry Cavill as Superman. To the contrary, Bale told Entertainment Weekly earlier this month he won't appear in a fourth film.
That's no matter, though: The next Man of Steel is said to feature the two characters relatively early in their lives as they grapple with their new superhero status, so a new Batman should be readily welcomed by viewers even if they're familiar with the existing franchise.
Better yet, Snyder also hinted that Batman may serve as Superman's nemesis this time around, as Man of Steel actor Harry Lennix took the opportunity to read the following passage from Frank Miller's 1986 comic book The Dark Knight Returns:
I want you to remember, Clark. In all the years to come. In all your most private moments. I want you to remember my hand at your throat. I want you to remember the one man who beat you.
Better better yet, The Hollywood Reporter also cited sources saying Warner Brothers has outlined tentative plans to release more DC-powered movies with The Flash in 2016, followed by The Justice League -- the DC universe's rough equivalent to The Avengers -- in 2017.
In the end, I suppose the folks at Disney probably saw this coming, but this news can't make the House of Mouse particularly happy now that Warner Brothers is finally ramping up their efforts to recreate Marvel's success.
But what do you think? Will Warner Brothers' new slate of DC superhero movies dampen the achievements of Disney's Marvel going forward?
In any case, it's also easy to forget this fight doesn't end with the big screen.
Fool contributor Steve Symington owns shares of Apple. The Motley Fool recommends and owns shares of Apple, Google, Netflix, and Walt Disney. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.