Warning: Minor SPOILERS for Tony Stark: Iron Man #13

With the mention of a single word, Iron Man has just dropped a cross-universe bomb on the world of comics--Tony Stark just confirmed that the DC's poster boy Superman exists in the Marvel Universe.

Marvel dropping subtle hints and jabs at the DC Universe is nothing new. But these interactions are usually left to those who travel across the Multiverse (or the fourth-wall breaking Deadpool). It's one thing for Spider-Man to leap into Metropolis, or even the Inhuman Lockjaw meeting Superman and Wonder Woman. And typically, stopping short of explicitly confirming the DC heroes, and counting on even the most casual of comic book fans to spot the red boots of Superman or the golden lasso of Wonder Woman. But Iron Man? He doesn't mince his words one bit.

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Now that Marvel has released the preview of Gail Simone and Paolo Villanelli's Tony Stark: Iron Man #13, fans can see the hero's direct reference to the world of DC Comics for themselves. Not a man to encounter many real obstacles he can't overcome, or challenges he can't rise to, Tony admits his apparent 'Achilles' heel: metaphysics. In the simplest terms, the philosophy of determining the 'true' nature of things (call it the curse of the scientific and mathematical genius). However, Tony uses a different term to get his weakness across...

Iron man Kryptonite

In his own words, Tony explains that he's "smart. Really smart. But it's a focused, narrow thing in a way. I see a problem, I blast it or buy it or give it robotic shoes. Metaphysics? That's my kryptonite." His meaning is easy to grasp, but it raises one major question for fans. How does Iron Man know about Superman or his famous weakness There are two possible options: either the trans-dimensional travel at work in the examples we mentioned above are frequent enough for Marvel's heroes to know of a parallel Earth's hero, Superman, and kryptonite's effects on him. Or, far more simple... the DC Comics Universe exists in Marvel's reality.

Now it's impossible to say if Marvel's biggest competitor in superhero comics is thriving in comic books, without their own biggest rival. Still, the confirmation alone is enough for fans to debate. What makes the reference even more interesting is Iron Man's later pop culture reference in this same preview--not the realm of superheroes, but famous wizardry. Tony uses the name "Dumbledalf" when his suit of armor gets an unexpected mystical boost, playing on the famous wizards Dumbledore and Gandalf of Harry Potter and The Lord of the Rings, respectively. Making a direct reference to DC lore, yet using a knockoff name to reference magic? Here's hoping the complete issue helps explain the differences.

Tony Stark: Iron Man #13 will be available at your local comic book shop on Wednesday, June 19th, or direct from Marvel Comics.

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