Doctor Strange’s final words to Tony “We’re in the endgame now,” left many people curious about exactly what he meant by that. The thing most people can agree on is that this endgame involved Tony Stark in some way, which is why Strange was willing to give up his Infinity Stone to save him. But what exactly does Dr. Strange expect Tony to do that will lead to Thanos’s defeat?
A lot of this information is going to be based off of supposed leaks about Avenger 4, seemingly titled Avengers: Endgame, so this is your spoiler warning for that before we jump in. A lot of more recent leaks about Endgame say that it’s heavily going to feature SHIELD again, with the Hulk seemingly in a SHIELD uniform and information pointing to Ton being involved in the new SHIELD. The idea for the endgame here being a play off of two things, Tony’s time as the head of SHIELD in the comics and his initial goal with Ultron. Could Tony be using SHIELD as just that, a SHIELD to defend the Earth should someone like Thanos show up again? Like with Ultron, this could be Tony’s plan to keep the world save from threats. It could be similar to his plans with the Initiative in the comics, training people and spreading them out around the world to keep more areas secured.
But Tony’s always been a man of action and sitting and waiting for threats isn’t going to get the 50% of all life back that Thanos destroyed. With SHIELD protecting the Earth, Tony may then focus his resources on an external attack force to go out into space to deal with Thanos again. A SWORD if you will. This could be a genesis of the comic book agency that defends Earth from extraterrestrial threats.
That’s just one idea, but another leak from a while ago factors in the time travel that’s been alluded to in the new film. The idea with this leak is that Tony is going to use his mechanical knowhow to build his own version of the Infinity Gauntlet, called the Stark Gauntlet. His plan, based on the leak, is to go back in time, presumably through the Quantum Realm, to the point in time when all the stones were initially discovered. So basically, they would be visiting previous points in the timeline from the various films the Stones premiered in to take the stones from there and, by doing so, somewhat altering the timeline. This would lead to a final showdown between the Infinity Gauntlet, used by Thanos who tracked them through time, and the Stark Gauntlet. Obviously, they would need Tony for this plan, since Tony stands the best chance among those left of actually creating something to wield the Infinity Stones.
Both of these are viable options that take advantage of Tony’s strengths as a character, so either could be the titular Endgame Strange spoke of.