Thanos has been manipulating many events in the Marvel Cinematic Universe, some of which backfired and saw the formation of Earth's Mightiest Heroes. But one mystery that was never fully answered questions what his actual plan was in Marvel's The Avengers.
It seems like a fan has finally figured it out what the Mad Titan was trying to do when he gave away an Infinity Stone in an attempt to get another Infinity Stone, but lost both in the process. It might not be canon, but if you're trying to justify the Mad Titan's actions, this will help:
[MCU] The events that lead up to the climax of Avengers 1 wasn't about Thanos wanting Earth or the Infinity Stones, it was all too destabilise Asgard from r/FanTheories
Of course, the Asgardians are some of the most powerful beings in the known Marvel Cinematic Universe, so it makes sense that Thanos needed to neutralize them before anyone else, even the Nova Corps.
It's unlikely that he'll go on a James Bond Villain-esque monologue and explain every facet of his master plan in Avengers: Endgame, but this fan theory does fill in a lot of gaps. And it's not out of the realm for Thanos to make these kinds of plans, as he is an intelligent being and a master tactician.
"Thanos has been lurking in the shadows with a desire to obtain these Infinity Stones, which has played a big part in our other films," said Feige. "We've introduced the Tesseract, revealed to be the Space Stone; the Mind Stone, which came out of Loki's scepter and then went into Vision's forehead; and the Time Stone: the Eye of Agamotto that Doctor Strange wears is an Infinity Stone itself! And of course the Guardians dealt with the Power Stone.
"So these storytelling devices that we've seeded into every film will continue to play a part and come together. We've been teasing this for six years. That's a long time to tease something cinematically before paying it off. Thanos has to be the greatest villain in our movies."
As for where he is at the start of Avengers: Endgame, and whether or not he has another grand design in place, directors Joe and Anthony Russo teased that the Mad Titan is simply relaxing now.
"He's succeeded in the thing he has set out to do," Joe Russo said to Empire Magazine. "He's done. He did it. He's retired."
Fans will see if Thanos stays out of the fight (not likely) when Avengers: Endgame premieres in theaters on April 26th.