If the 15 "Summer 2015" teasers Marvel released over the past several weeks, plus the "EVERYTHING ENDS" in Spring 2015 teaser from Tuesday are indeed related to "Secret Wars" as many suspect, then the publisher is prepping for a massive event -- possibly the biggest one its ever undertaken.

While it's been established that writer Jonathan Hickman is building towards the event in the current "Time Runs Out" storyline in "Avengers," that just doesn't feel quite big enough. Alex Ross' teaser image presents a cosmically epic battle between characters from multiple Marvel Earths, and the just-released cover by series artist Esad Ribic homages Mike Zeck's original "Secret Wars" #1 cover with a mix of heroes and villains from both the 616 and Ultimate universes. Factor in the over-a-dozen different realities showcased in Marvel's line of Summer 2015 teasers, and there remains little doubt that as big as the Avengers are, Hickman and Ribic's story aims to be even bigger.

Marvel's got a history of launching its events out of the major storylines of its ongoing series, so it's understandable that fans have been looking at the "Avengers" almost exclusively for "Secret Wars" clues. After all, the current "AXIS" event spun directly out of the pages of "Uncanny Avengers," and "Spider-Verse" has been set up in "Amazing Spider-Man" for months. Yet if you take a step back and look at the entire Marvel line of titles, there are strong indications that "Secret Wars" is something different -- and more expansive -- than the normal Marvel event.

"This is a huge story," Editor-in-Chief Axel Alonso told CBR TV in October. "It's a universe-spanning event. It's big enough that every time we've planned another event for the last several years, from 'Original Sin' to the current 'AXIS,' we've had to consider how this might affect 'Secret Wars.' So this is a big one."

The question remains, how big does Alonso mean? Well, with a little bit of deductive thinking and some digging through past interviews and back issues, we've become convinced that "Secret Wars" is indeed going to be pretty damn big. Here's what we're thinking.

Jonathan Hickman's "Avengers"

Don't get us wrong -- we're not saying Hickman hasn't been laying the groundwork for "Secret Wars" in his Avengers books these past few years. Even if Alonso hadn't verified as much -- saying, "The early ideas of Jonathan were brought to us prior to him coming on 'Avengers,' and when he took on 'Avengers,' we all knew he was building to this moment" -- we'd still agree that the events in those books are direct precursors to Hickman and Ribic's upcoming story. After all, the Incursions -- space/time "contractions" which have forced Earths from various realities to merge, resulting in the unavoidable destruction of both planets -- are a perfect plot point to build a multi-dimensional series. But who's to say that we've only been seeing the fallout from these Incursions in "Avengers"? It's certainly not out of the realm of possibility that other cross-dimensional events have been caused or affected by them, playing out in other series' storylines.

Plus, if you haven't noticed, Hickman's expansive Avengers roster includes not only the classic Avengers, but also a Hyperion -- an all-new version, from a never-before-visited dimension's Earth -- and several characters who, while not from the New Universe, do sport very strong resemblances to characters from the non-616 Earth introduced back in 1986 during Jim Shooter's tenure as Marvel editor-in-chief. And that "EVERYTHING ENDS" teaser certainly evokes the sense of the "White Event," which originally spawned the New Universe nearly 30 years ago.

It also certainly helps that Sue Storm and Reed Richards currently play a pivotal role in "Time Runs Out" -- and those are two characters that Hickman has worked with extensively in the past. But more on that later.

Brian Michael Bendis' X-Men

During the Marvel Unlimited Plus members-only event at New York Comic Con, Brian Michael Bendis -- who writes both "All-New X-Men" and "Uncanny X-Men" -- told the audience, "Both ['Uncanny' and All-New'] are heading straight into 'Secret Wars.'" At the time, the statement read as a simple acknowledgement that Hickman and Ribic's event would have line-wide repercussions since "Uncanny's" storyline is taking place solidly in the 616, even though the "All-New" team have found themselves stranded in the Ultimate U (a place Bendis is very familiar with, having written in the alternate universe since the very beginning, 2000's "Ultimate Spider-Man" #1).

But with several Bendis-written characters appearing so prominently on the first "Secret Wars" cover reveal -- especially Miles Morales and the "All-New" Jean Grey, who along with her team relocated from the past to the present in 2012 -- we're looking at that statement in a new light.

We still don't have a clue as to how the time-displaced X-Men from the past managed to find themselves in a whole other reality. Could an Inversion be gearing up to take effect between the 616 and Ultimate Universes? Or could it have something to do with Matthew Malloy, a mutant introduced in recent "Uncanny X-Men" issues, with a a virtually immeasurably strong power set that is not unlike that the Beyonder, the character that sparked the original "Secret Wars"?

Discovered by Charles Xavier years ago, Malloy's power was so strong that Professor X actually opted to suppress it rather than attempt to train him. With Xavier dead, Malloy's powers have emerged, and he's making and remaking his personal reality as he sees fit. Bendis has said the events of "The Last Will and Testament of Charles Xavier" would be massive, leading to a "completely different" X-Men franchise, and with "Secret Wars" hyped by Alonso as an event designed to effect every single Marvel title, there's a solid chance the two will collide in a big and meaningful way.

"Cataclysm" and "Spider-Men"

Speaking of Bendis, the steward of "Ultimate Spider-Man" broke down the long-built barriers between the Ultimate Universe and the Marvel Universe both with "Spider-Men" and then again with "Cataclysm: The Ultimates' Last Stand" -- bringing Galactus, Eater of Worlds, into the Ultimate U. By the end of the event, the heroes proved triumphant, bringing down one of the biggest threats the Marvel U has ever seen. However, the absence of power is going to leave a vacuum, maybe even weaken the barrier between realities further. "Cataclysm" was directly responsible for the Ultimate U's scientists wanting to continue to explore the two realities, which led directly to the current "All-New X-Men" storyline.

Plus, there's also Joshua Hale Fialkov's "Ultimate FF," which ended up focusing on exploration of other universes and also came out of "Cataclysm." And there's that "Spider-Men" sequel that's been discussed for a while...

Jonathan Hickman's "Fantastic Four" and "FF"

In 2010, Hickman's "Fantastic Four" run was in full swing, with a number of Nathaniel Richards from multiple universes (sensing a theme here?) battling it out Highlander-style for the right to be the sole version of Reed's father across all of time and space. In the midst of all of that, Sue and Reed's children, a fully grown Franklin and Valeria, show up in the present from the future to warn their parents about what's to come. What appeared at the time to be a discussion between Val and her mother about the then-current multi-dimensional threat takes on a whole new meaning when viewed by the light of the impending "Secret Wars" -- especially given how much Hickman seems to like playing the long game.

"Spider-Verse"

The various Spider-Men and Women have been dealing with their own personal Incursions over the last half a year or so in the form of the Inheritors, a powerful, long-lived family dedicated to hunting down the Spider-Persons of every dimension they can find, killing them and absorbing their essence. While relatively self-contained so far, "Amazing Spider-Man" #7 directly acknowledged the Incursions being dealt with by the Avengers, the first time the Earth-destroying phenomena have been acknowledged outside of Hickman's books, as best we can recall.

Is it possible it's just a coincidence Marvel is publishing two high-profile multi-dimension-spanning events at the same time? Of course it is -- but with the long game Hickman's been laying out, and the overt mention of one event in the pages of the other, our money's on the two being more closely related than it may appear. In fact, in an upcoming Spider-Mandate interview with series editor Nick Lowe, he spoke about the importance of the Master Weaver, and the designation of an Earth-001. "It's an Earth that Dan [Slott] has certainly been developing for a while, just in the process of working up this story," Lowe said. "It's a very, very important Earth because of the character who calls it home, the Master Weaver, who we've just teased up to this point in a backup story in 'Superior [Spider-Man]' #33. You'll be seeing him a lot more as the story goes on. He's a very important character to the multiverse and to this 'Spider-Verse' story."

Rick Remender's "Uncanny Avengers"/"AXIS"

Another writer accustomed to playing the long game with his plotting, Rick Remender's current "AXIS" event has its roots extend even further back than the start of "Uncanny Avengers," all the way to his 2010-launching "Uncanny X-Force" series. And while "AXIS" is most likely the culmination of the majority of his plot points, the effects of any major Marvel event are designed to be felt for months or years after the final issue has been collected.

While the "Uncanny Avengers'" pre-"AXIS" story arc was more about time travel than other dimensions, it did present a separate Marvel Universe from the main 616, and even after the other reality was nullified, some of the effects of the events that occurred there linger on, including the pain Havok and the Wasp feel over the loss of their daughter. Typically speaking, these alternate reality storylines resolve themselves with the participants forgetting what happened completely, or struggling to recall specifics as the details wash away swiftly in the repaired reality. However, not only do Alex Summers and Janet van Dyne remember their daughter, the feelings they developed for each other while in the other world have remained, possibly indicating a further weakening of the walls of Marvel's realities.

"Original Sin"

As mentioned earlier, Axel Alonso has made it very clear that "Secret Wars" has been on the agenda for so long that several of the company's previous event stories were built with the knowledge that it was on the horizon. And Marvel's most recently concluded event, "Original Sin," may be no exception. After all, that event revolved around the murder of Uatu, The Watcher -- the big-headed alien tasked with observing the Marvel Universe. At the end of "Original Sin," the original Nick Fury took on a Watcher-type role as "The Unseen," but a major question still emerges -- without Uatu around keeping an eye on things, does that mean the potential for multi-universal calamity will go unchecked? Also, keep in mind what's perhaps Uatu's most famous role in Marvel's publishing line -- that of narrator of the old "What If...?" series. That series was all about alternate takes on Marvel history, and without Uatu around, it's not out of the question to wonder if some of that might start seeping together.

"Age of Ultron"

A year before "Original Sin," some serious cracks in the Marvel Universe seams started to show in the Brian Michael Bendis-written "Age of Ultron." The event began with one altered timeline before shifting to another, before time changed once more to get things back to "normal." But that wasn't without its cost -- in a four-page sequence, the effects of mucking with the timestream were shown, with characters like Wolverine and Iron Man confronted with visions of past and alternate versions of themselves, and images of everything from the Marvel Zombies world (which has been fertile territory for dimension-hopping in the past), the MC2 (home to "Mayday" Spider-Girl) and 2099 timelines, post-apocalyptic future character Killraven and more. The impact was immediate: Galactus from the classic Marvel Universe showed up in the Ultimate Universe (sparking "Cataclysm"), and Angela -- a "Spawn" character created by Neil Gaiman and Todd McFarlane that landed at Marvel following legal maneuvering -- landed in the MU proper, after previously existing in an entirely different company's fictional world.

"Age of Ultron" was merely the splashiest of recent Marvel time-travel stories, including Spider-Man 2099 taking residence in the contemporary timeline, and the original five X-Men setting up seemingly permanently in the present. A conversation between Beast, Iron Man and Hank Pym in the denouement of "Age of Ultron" #10, the last issue of that series, lays it out rather cleanly: "We broke the space-time continuum," Tony Stark says. "We're teetering on multiversal chaos." We may not know much about "Secret Wars" yet, but "multiversal chaos" sure sounds like an apt description of what's been revealed and hinted at so far.

Plus, there's the "Marvel Zombies vs. Age of Ultron" image from Marvel's recent round of teasers -- which are, again, widely considered to be "Secret Wars"-related -- was released a couple weeks back.

Senior Editor Stephen Gerding, Managing Editor Albert Ching and Editor Steve Sunu contributed to this report.