Within the Marvel Cinematic Universe, the Infinity Stones have unquestionably been the biggest MacGuffins, and six years after his introduction, Thanos finally succeeded in obtaining all six of these powerful, multi-colored artifacts. Now Thanos is now the most powerful being in the MCU, hence why he was able to wipe out half of all life in an instant. However, Avengers: Infinity War and Avengers 4 co-writer Christopher Markus assures fans that this doesn't make the Mad Titan undefeatable, and there is a weakness when it comes to the Infinity Stones. Markus explained:
Let's not undersell this: undoing what Thanos did at the end of Avengers: Infinity War will be the hardest endeavor yet for the surviving heroes in Avengers 4. And even though he seems to have left his days of spreading death and destruction behind him now that he finally accomplished his goal, you can bet that once Thanos learns that there are people seeking to destroy his "work," he'll do whatever it takes to ensure they fail doing this. All this being said, Christopher Markus suggested Avengers 4's heroes can get at least one of the Infinity Stones away from Thanos, that's the first step towards achieving victory.
As Christopher Markus pointed out in the book Marvel's Avengers: Infinity War - The Art of the Movie (via Comicbook.com), there have been several instances of folks who've wielded just one Infinity Stone not properly harnessing its power. Doctor Strange and Vision could be considered exceptions, but when Avengers: Infinity War rolled around, it didn't matter because Thanos was able to put all six into his Infinity Gauntlet. He's the first individual who's been able to use the Space, Power, Reality, Mind, Time and Soul Stones to their full potential. That's all well and good for him, but from a storytelling perspective, it paints these characters into a corner. How can they beat someone who's practically invincible?
There's already been plenty of speculation on how time travel, via the Quantum Realm, will play a role in undoing Thanos' genocide, but that doesn't deal with the fact that the Mad Titan still has all six Infinity Stones at his disposal. The Infinity Gauntlet was damaged after Thanos snapped his fingers in Wakanda and turned so many to dust, but the Infinity Stones appeared to be intact, so one would imagine that he can still harness their power. Taking each Infinity Stone is an interesting plan, but how are the Avengers 4 heroes supposed to do that if Thanos can incapacitate them in an instant?
My guess is that when Thanos carried out universal genocide, that did damage the Infinity Stones. He can still use each of them, but only one at a time rather than a few or all at once. If that's the case, then while Thanos is still quite powerful, but at least the heroes would still stand a better chance (if only slightly) of taking the Infinity Stones from him and bringing him down. Personally, I would try to steal the Time Stone first so that Thanos can't rewind and make sure events happen as he sees fit, like he did when Scarlet Witch successfully destroyed the Mind Stone.
Stealing at least one of the Infinity Stones could also come in handy if Iron Man and the gang are indeed venturing into the Quantum Realm. It's unclear if the reason Scott Lang, a.k.a. Ant-Man, didn't disappear in Ant-Man and the Wasp's mid-credits scene is because the Quantum Realm is shielded from the effects of the Infinity Stones or if Scott was simply one of the lucky half that survived the Snappening. If it's the latter, then what's to stop Thanos from simply halting the heroes in their tracks once he learns they're inside this other reality? Taking one or a few Infinity Stones off the proverbial table ahead of time would boost their chances of succeeding in changing the timeline.
Since characters like Spider-Man and Black Panther are confirmed to be starring in their own Phase 4 movies, we know that at least the heroes who were dusted at the end of Avengers: Infinity War will be brought back, and hopefully the same proves true for all the civilians who were erased too. The question is how that will happen, and even with only six months to go until Avengers 4's release, plot details are still shrouded in secrecy. But if they're going to win the day, those Infinity Stones will definitely need to be dealt with sooner rather than later.
As for Thanos, since the good guys will somehow emerge triumphant, that means he'll ultimately be defeated. But again, how that will be accomplished remains to be seen, as well as whether or not he'll make it out of Avengers 4 alive. For now though, Thanos is enjoying his retirement on that unnamed, serene planet, happy that he was finally able to bring about "true balance" to a universe that, in his opinion, was going to be ravaged by overpopulation. Alas, he won't get to be content for much longer.
All our questions will be answered when Avengers 4 is released in theaters on May 3, 2019. Stay tuned to CinemaBlend for continuing coverage and be sure to look through our Marvel movies guide to learn what else this superhero franchise has coming down the pipeline. Or you can look through our 2019 release schedule to learn what non-Marvel cinematic offerings arrive next year.