With the premiere of End Game quickly approaching there is a lot of discrepancies and doubts coming into the film. I have come up with a few theories my self and listed them out below.
How will the avengers attempt to reverse everything?
There are a few major theories going around as per the Avenger’s solution to the decimation. One theory goes that time travel will be used to some extent and the team will go through time to solve their issues. How this will be executed? Is a good question.
Another theory states that the Quantum realm is a major plot point that will enable team to defeat Thanos. I don’t have any ideas as per how this will occur or why they would use the Quantum Realm, but it will sure come in handy as it appears that the power of the Infinity Stones does not seem to work in other realms outside of their own.
Lastly, we will be pleasantly surprised. If Infinity War taught me anything is that Marvel knows how to tell a story and still be surprised. Although we knew coming in there was going to be big ramifications for the events that will occur after the film, this film will very likely have elements to it that we were not expecting, plot twists that will work well (similar to the Skrull's plot twist in Captain Marvel).
One major plot question is how much time will have passed from Infintity war to End game. If a few weeks pass then no big deal everyone is back. But it would be interesting to see a withered universe recuperating from a year long plus attempt to re-establish itself after loved ones disintegrated.
Who dies?
Since no major deaths have occurred up until infinity war (farewell well Heimdall, Loki, and Vision) it is often speculated that those who died outside of Thanos’s Snap are dead as dead can be. Those who turned into dust are speculated to return, especially since Peter Parker has a new movie coming out this year, Black Panther earned over $1 billion in the box office and was nominated for the Oscars so it would be insane for this character not to come back. But among those characters with high probabilities of meeting there end are: Captain America (Steve Rogers) and Iron-Man (Tony Stark). In the Comics Steve Rogers should have died in Civil War, and a major rumor went around that he was perishing then. However, that was no the case. Tony Star started this first trilogy of phases in the MCU and it would only be fitting that he ends it prior to Phase IV. Both the Cap and Iron man are major juggernauts in the MCU and it would only make sense that they make the ultimate sacrifice and die for the greater good of the Universe.
Who comes back from dust?
Everyone. Nuff said.
Who will be the next baddy?
There are a few major villains that could either come by and replace Thanos, or be a intermediary villains similar to Loki and Ultron. My speculation is that Dr. Doom will be the a intermediary villain sometime around Phase IV as Kevin Feige and Company figure out how to incorporate the Fantastic 4. We would also see the likes of Magneto causing a fit later in the Phases. But most likely we will see Galactus, the devourer of worlds, as the next major villain, especially since his rights fall under Marvel and not Fox. This under the assumption that the next villain has been planned well in advance before the Fox deal.
Whats next?
With the Fox deal officially in place there is no doubt that the X-men and Fantastic 4 will be making their MCU debut sometime in the near future. There is no way that Marvel will not have a combined Cinematic Universe with the likes of Wolverine and The X-Men. Dead pool will also very likely be breaking the 4th wall sometime around late Phase IV or more likely, Phase V. It is also likely that we will see the Likes of Miles Morales have his own solo flick, however since Sony owns the rights to Spider-man, I am not sure how this will play out. I personally hope Dare devil can be revived and somehow the Defenders can make at least a Cameo in future installments of the Avengers.
Far into the future I suspect that multiverses will be explored and alternate versions of our favorite super-heroes/villains will team up to defend the multi-verse.