The most successful franchise of all time (with more than $10 billion worldwide at the box office), the MCU is flourishing on the silver screen as well as on the small screen. Each and every day the fans are treated to some new pieces of information regarding their favorite Marvel superheroes, from heavy hitters like Thor to the ones who possess no special abilities at all, like the Punisher.

Besides the official news, the web is filled with rumors concerning what might happen next. Whether they come from sources that have proved themselves reliable, or they seem to be just pieces of fan-fiction, all of these rumors show the interest the fans have in these productions. Given the high-quality of the stories presented, it is no wonder that they catch everybody's attention.

So what are the latest and most credible rumors concerning the MCU? If you want to find out, you've come to the right place. But, as always with any rumors, there may be some huge spoilers!

Heimdall and Skurge will die

It won't be called Thor: Ragnarok for nothing - after all, it is all about Asgard being destroyed and the Asgardians perishing. However, it is very unlikely for the entire race (save for Thor) to disappear. So, most likely, we will be shown just a few big deaths on the big screens.

And, obviously, one of those will be the death of Heimdall. Whether it will be Hela, Loki, or some other villain (Surtur is also rumored to appear), Heimdall needs to disappear. Besides being one of the most powerful Asgardians, he is also the gatekeeper, the guardians of Asgard. So he'll have to be disposed of pretty soon in the movie.

Will it be Loki to do it, as soon as Heimdall realizes that Odin is gone?

Skurge is also an antagonist in Thor: Ragnarok and he'll be portrayed by Karl Urban. As it happens in the MCU, he'll die. But, as the rumors say, he will die after betraying Hela and joining the Asgardians. So this is yet again something else that has all the chances to happen.

Doctor Strange and Dormammu

One of the most recent rumors (as well as one of the oldest) says that Dormammu will be the next villain in the Doctor Strange franchise. Furthermore, given how powerful the ruler of the Dark Dimension is, it has also been speculated that he might be the big baddie of the MCU, as soon as Thanos is defeated.

As said, this is both an old and a new rumor. Thus, even the description of Kaecilius teases it, with Dormammu most likely using this C-list villain as a vessel into our world.

Most recently, though, it was (almost) revealed that the supervillain will appear as early as this year - you can check out the entire news piece here. So, at this point, this seems like a safe bet - unless Marvel is playing with the fans.

Given that Mordo will also turn up as a villain, someone should be there backing him up. So why not Dormammu? If I were to bet, I'd most certainly put all my money on this. It’s about time the Avengers faced someone with mystical powers.

Iron Man 4 is happening

Quite a while ago, while promoting Captain America: Civil War, Robert Downey, Jr. said that he might do another Iron Man flick. Which was great from more than one point of view, given the rather disappointing storyline of Iron Man 3 (come on, you also want to see the Mandarin rise in the MCU).

Well, it appears that Kevin Feige is actually on board with this idea. And he isn't alone, since Jon Favreau seems to be back in the MCU.

About a week or so ago, Robert Downey, Jr. tweeted a very interesting pic teasing a new project. Kevin Feige, the Russos, and even Tom Holland are in there. What could it be? It certainly isn't another Spider-Man movie so soon, right?

 

New project @Jon_Favreau and @RidingShotgunLA are working on!

(Photo cred: @jimmy_rich, Glam cred: @DavyNewkirk) pic.twitter.com/yUh0L2A34U

"” Robert Downey Jr (@RobertDowneyJr) September 12, 2016

Well, I'm keeping my fingers crossed for this one. RDJ is known to be quite a kidder, so that could be just a meeting between friends. But, but, do I want a 4^th (and final) Iron Man flick, to end the franchise with a bang!

Here's something interesting: nothing can top NOT having Pepper Potts defeat the villain in the silliest way possible"¦

Zendaya isn't Mary-Jane Watson

As far as Spider-Man: Homecoming is concerned, there are plenty of things we know, as well as plenty of things we aren't so sure about. Zendaya falls in the latter category. At first, it was rumored that she will portray Michele Gonzales, who had a fling at one time with Peter Parker and who was also his roommate.

But then it was (almost) officially confirmed that she will in fact portray Mary-Jane Watson, which seems to me to be a politically-correct decision, if true.

Well, it was almost confirmed. The most recent rumors say that Zendaya is indeed portraying Michele and that she will be just a fling before Peter Parker finds his one true love. And that is great, as far as I am concerned, since this gives more depth to the relationship.

Furthermore, having Zendaya as Michele does open some interesting possibilities for the future of the Spider-Man franchise. I guess I am not the only one who wants to see villains like Chameleon on the big screen"¦

Death and Hela

One of the most recent rumors concerning Thor: Ragnarok is that it will reveal the whole reason why Thanos is after the Infinity Stones. Thus, just like in the comics, the Mad Titan is infatuated with Death. However, unlike in the comics, the MCU won't introduce this powerful cosmic entity.

And for good reason - until now, no other cosmic entities have been introduced. Furthermore, having them in the shared universe could confuse the general audiences (the ones that bring the big bucks, that is).

So, in the MCU, an adaptation will be made and one of the villains of Thor: Ragnarok will become Death. And that villain is Hela, the ruler of Hel, portrayed by Cate Blanchett. And this would be great - the actress would be wasted if she appeared just as a villain in a single MCU flick. Whereas her skills will be put to better use if she became a constant in the shared universe.

I actually want to see this happening. Don't you? Marvel needs to make this happen!

The Eye of Agamotto is an Infinity Stone

There are several clues hinting that an Infinity Stone, namely the Time Stone, will appear in Doctor Strange. And the biggest is when the Ancient One says that she has been searching for Strange peering through time and that she can see his future.

Of course, this is just a rumor - the same as any on this list. However, besides a possible big baddie for the entire MCU, Doctor Strange also needs a bigger connection with the rest of the shared universe. And what better connection could there be than an Infinity Stone?

This could also mean that Strange will be robbed of one of his most powerful artifacts when Thanos arrives. However, there is a way around this, if the Sorcerer Supreme becomes the keeper of the Time Stone.

Could this rumor turn out to be true? Everything is possible at this point. But I am more inclined to believe that the Eye of Agamotto is indeed an Infinity Stone, since it also gives Doctor Strange all the more reason to give his best against Thanos.

Infinity War will be missing some heroes

There are plenty of heroes in the MCU. Besides the original roster of the Avengers (Iron Man, Thor, Captain America, Black Widow, Hawkeye, and Hulk), there are also the newcomers (Ant-Man, Vision, Scarlet Witch, Falcon), those from other worlds (Guardians of the Galaxy), and those who haven't appeared on screen just yet or aren't included in any team (basically, the rest of them).

So there are quite a few characters the Russos have to tackle, besides the eventual additional villains.

So this rumor is a safe bet - Avengers: Infinity War won't feature all of these heroes. Most likely, the original roster and the newcomers will be present (and this is still quite a few characters), with cameos from the likes of Doctor Strange, Captain Marvel, and Black Panther.

And this is great - and quite understandable. After all, the Russos may want to keep something for the fourth Avengers movie, as well. And then everybody (who survives, of course) will be in, with the other superheroes joining the fight, as well.

Steve Rogers dies in 2018

Of course, having Vision bite the dust as soon as Thanos arrives is a given - after all, one of the Infinity Stones is etched into his forehead. However, a big surprise would be if one of the big Avengers dies. And everything points to Steve Rogers, who isn't even Captain America any longer.

It can't be Robert Downey, Jr., because he is the face of the MCU. And, even if he costs a bit too much, his cameos would certainly bring the fans to the cinemas. Thor, on the other hand, is a godlike being. And, even if he dies, he will most likely be resurrected as someone else. Plus, his death wouldn't surprise anybody, given the poor reception of his movies.

On the other hand, Steve Rogers could prove with his death that the Avengers should be united and shouldn't be under anybody's supervision. So I do expect him to give his life in a heroic way toward the end of the Infinity War. And this would lead to a fourth Avengers flick, in which everybody would have even more reasons to fight with all their strength against the Mad Titan.

Avengers 4 will be the last with the current roster

Although unconfirmed, this is actually certain - Avengers 4 will be the last ensemble movie of the MCU to focus on the original roster of superheroes. So it will be then that we'll say goodbye to Iron Man, Thor, Hulk, Black Widow, and Hawkeye.

It makes sense to happen this way, given the host of new superheroes who will arrive in Phase III, starting with Doctor Strange. And this could make way for other teams of superheroes, such as the Illuminati. Yes, I know that Marvel still lacks some rights to some of the characters, but the roster could change.

After all, they managed to make history on the big screen with second-tier characters such as Iron Man and Thor (second-tier when compared to Spider-Man, Fantastic Four, and X-Men, of course).

And who knows? Maybe Scarlet Witch will undo the entire universe at some point and the characters Marvel doesn't own today will pop up as if it were magic!

Sharon Stone, Christoph Waltz, and Kevin Hart

This one is quite old - Sharon Stone will be yet another Hollywood star to join the ever-expanding cast of the MCU. The actress herself teased this possibility when she said that she'll have a tiny role in an upcoming Marvel flick. Obviously, she must have been talking about the Ant-Man and the Wasp sequel, in which she'll most likely portray the first Wasp, who got lost between dimensions.

As far as Kevin Hart is concerned, he is also rumored to appear in the Ant-Man sequel. But I wouldn't bet on it. Even if his movies bring money and even if he is an A-lister, Ant-Man already has the awesome Michael Peña playing the comedic sidekick.

Christoph Waltz is yet another big name rumored to be added to the cast of Ant-Man and the Wasp. However, nothing has been confirmed. And, quite frankly, Waltz has already portrayed his share of awesome villains on the big screen. So maybe he should pass on this opportunity (especially since Marvel isn't exactly known for its great villains).

The Punisher may arrive in 2017

Lastly, going to the darker corners of the MCU, the most recent reports say that Jon Bernthal is busy on the set of a Netflix show. Does that mean that The Punisher will arrive in 2017, as the third Marvel flick of the year on Netflix, as some previous rumors said? Or is he shooting for The Defenders? Is he making a cameo in Iron Fist?

Anything is possible. However, I am more inclined to believe that he'll be a part of the Defenders roster. It's a bit too early for the Punisher series to be released, especially if we take into consideration the amount of time it took for the others to be made.

However, I wouldn't frown if The Punisher was released in 2017.

Sylvester Stallone

Obviously, the biggest rumor out there is that Sylvester Stallone will bring a Ravager to life in Guardians of the Galaxy: Vol. II. Given his action-hero roles thus far, it certainly fits him. And that even if we don't know if he'll be a part of Yondu's former crew or if he'll have a crew of his own.

However, there is another rumor which might come to life. Yes, Stallone is best known for his action roles. However, he is also an old guy and so he might have wanted a different role for himself this turn around. Thus, the rumor says that he will in fact be one of the Elders of the Universe, pretty much like the Collector and the Grandmaster (portrayed by Benicio del Toro and Jeff Goldblum).

And I like this rumor more, because it will expand the mythology of the Elders within the MCU. What Elder could Stallone portray? It is anybody's guess.

In any way, this rumor would further connect the Guardians of the Galaxy with another upcoming movie, respectively Thor: Ragnarok. Which is great!

Doctor Strange will cameo in Thor: Ragnarok

This rumor is based on a tease from Chris Hemsworth and Taika Waititi on the set of Thor: Ragnarok. I guess you have all seen the main star holding a card with the address of the Sanctum Sanctorum. The director didn't confirm that Doctor Strange will appear in the flick. But, at the same time, he didn't deny it.

So the rumor says that Doctor Strange will cameo in Thor: Ragnarok. Most likely, after finding Odin on the streets of New York, Thor will ask the Sorcerer Supreme for his help. And this might just be the way in which the God of Thunder finds his way on the planet ruled by the Grandmaster.

Obviously, this is just speculation. And we haven't heard anything about Benedict Cumberbatch being on the set of Thor: Ragnarok. But it would certainly be a big surprise if Thor receives some help from a fellow superhero (other than Hulk, of course).

Could this happen? It is most likely. But we'll have to wait some more in order to find out the truth.

Kingpin will cameo in The Defenders

Whether a rumor or an obvious guess, this has all the chances of happen. Thus, on the web it is said that Vincent D'Onofrio will cameo (at least) in the upcoming The Defenders. Obviously, there is no official word that the actor will be included in the 2017 show. But how many of you were caught by surprise when the Kingpin appeared in the second season of Daredevil?

And this appearance would fall in line with the events of this year's second season. Thus, even if the Kingpin is still in jail, he can get out whenever he wants. However, he is waiting for the heroes to clear the streets for him. When will that happen?

Obviously, in the Defenders show, when the team of superheroes will most likely go against the Hand. And once the Hand is obliterated, the Kingpin will appear, ready to once again rule the city.

As said, this would be anybody's guess. And since we have all seen the Netflix/Marvel shows, this has all the chances to happen.

Fox will deal with Marvel

Wishful thinking or just a baseless rumor, it is all the same. But I guess everybody wants to see Marvel making a deal with 20^th Century Fox over some of the characters owned by the latter studio. This has been something the fans wanted to see ever since Spider-Man joined the MCU.

However, last month, the rumor was reignited, when Matt Key (producer of the Fatman on Batman podcast with Kevin Smith) said that Marvel and Fox did discuss over some of the characters. Granted, it may not be the X-Men, just like it may not be the Fantastic Four (even if Fox has kept silent as far as Marvel's first family is concerned).

And I am ok with that. So, if the rumor is true, maybe Marvel will finally get the rights back to some other properties, such as Galactus, Doctor Doom, Kang the Conqueror, and so on. Yes, Marvel needs these villains. Especially if Dormammu won't be the future main antagonist of the MCU.

What do you think? What other credible hot rumors about the MCU should be on this list?