Warning: MASSIVE spoilers ahead for Thor: Ragnarok! You've been warned!
Thor: Ragnarok has finally debuted, which means audiences have now laughed, cried, and generally had a phenomenal time with arguably the best Thor movie ever made. Taika Waititi has directed a tremendous self-contained story about destiny, family, and intergalactic gladiators, but in the grand scheme of things, it's only a stepping stone to something much more significant: Avengers: Infinity War.
With Thor: Ragnarok now in theaters and becoming a box office juggernaut, now is the time to dive in and discuss how this film will directly set up the events of Avengers: Infinity War. We have a few moments to get to, so let's kick this off by discussing how Loki's encounter with a familiar Infinity Stone will tie into the next Avengers movie.
Loki Steals The Tesseract
Ever since the end of Joss Whedon's The Avengers, the Tesseract has been safely nestled in Odin's trophy room on Asgard for safe-keeping. However, that changes in Thor: Ragnarok when Loki enters the vault during the mission to unleash Surtur and take Hela down. We see him stare longingly at the powerful, glowing cube when he enters the room, and the implication is that he smuggles it out in the confusion of Asgard's destruction. Early footage of Avengers: Infinity War has already confirmed that Loki will actually give the Tesseract to Thanos in the next major Marvel team-up, but it remains unclear if Loki is handing the cube over willingly, or if he's merely giving in so he can live to fight another day.
Banner May Be Gone
Banner's ability to switch back and forth from Bruce to Hulk without batting an eye is something that the Marvel Cinematic Universe has taken for granted over the last decade. Now, with Thor: Ragnarok, that may no longer be the case. Banner remained Hulked out on Sakaar for two years, and he made it very clear to Thor that one more episode could potentially give the green guy total control. That said, when push comes to shove, Banner decides to let Hulk take control to help defeat Hela -- but it's never truly established as to whether or not Bruce Banner can even come back at all. Mark Ruffalo has teased Ragnarok as the beginning of a trilogy for Banner, so the evolution of this struggle may play a prominent role during the events of Avengers: Infinity War.
Mjolnir Is Destroyed
A significant portion of Thor: Ragnarok's final act is meant to set up the fact that Thor Odinson does not need his trusty hammer in order to be the hero that we have all come to know and love. That said, the fact that Hela has destroyed Mjolnir (and it doesn't look like it's coming back for a while) still has some pretty bad implications for Infinity War. Not giving one of the most powerful Avengers one of his most powerful weapons very clearly means that Thor won't be quite as mighty as we have typically come to expect over the years (no flight, no ability to immobilize his enemies, etc.), so the Point Break Avenger will have to fight that much harder when the big, purple baddie comes to town.
The Destruction of Asgard
In the same way that the destruction of Mjolnir puts Thor at a disadvantage in Avengers: Infinity War, the destruction of Asgard similarly puts Earth in a position in which it will have to rely on its own armies. We already know that T'Challa will enlist Wakanda's troops (not to mention Cap and Bucky) to battle Thanos' armies, but it's hard to deny that it would've been nice to have an entire planet full of super-powered soldiers who could show up via the Bifrost and kick some ass. The Asgardians are now in complete and utter disarray after the game-changing destruction of their homeworld, which means reinforcements are not coming over the hill for The Avengers and the Guardians of the Galaxy. Our favorite heroes are on their own, which significantly raises the stakes of Infinity War.
The Death of Odin
Along with the destruction of Mjolnir and Asgard, the passing of Odin puts our heroes at a substantial disadvantage when Avengers: Infinity War rolls around. Even at his advanced age, Odin was one of the most influential warriors in the entire Marvel Cinematic Universe, and his reign meant something across the Nine Realms. The death of Odin implies that a very significant reinforcement cannot get in on the action to help our leading heroes square off against Thanos, which could have a major impact on the outcome of the battle. Losing one of the most powerful beings in the universe is never a good thing (mainly when he is your father and a close ally), so you can bet that the fallout from Odin's death will have implications on Thor's personality and his ability to fight back.
Thanos Finds Thor In Space
Although he doesn't make an official on-screen appearance during the events of Thor: Ragnarok, Thanos' presence is heavily-implied during the film's mid-credits sequence in which the Asgardian refugee ship encounters a much, MUCH bigger ship out in the recesses of space. From this moment, we're meant to take away the fact that Thanos and his Black Order seem to have found the first of many heroes that they intend to kill in their mission to "court death." In fact, one could assume that this mid-credits sequence will naturally lead to the Avengers: Infinity War trailer in which Star-Lord and the rest of the Guardians of the Galaxy find Thor floating through space. No word on what happens to the Asgardians in this scene, but let's hope Loki uses the Space Stone to help.
Asgard's Infinity Gauntlet Is A Fake
The Infinity Gauntlet has created a notable incongruence in the Marvel Cinematic Universe because its exact location has remained somewhat inconsistent over the years. The glove made its first official appearance in the MCU in the background of the original Thor, thus implying its location safely within Odin's trophy room. However, the post-credits sequence to Avengers: Age of Ultron implied that Thanos had already obtained the weapon at another (still undisclosed) location. Thor: Ragnarok manages to fix all of those storytelling issues by having Hela explain that Odin's Infinity Gauntlet is cheap forgery with no significant powers or abilities. Thanos' gauntlet is the one true gauntlet, which means he already has it when Infinity War starts. No need to attempt to retrieve it on Asgard; he can simply go straight for the Infinity Stones.
Thor Meets Doctor Strange
One of the funniest scenes in Thor: Ragnarok (which is seriously saying something) also happens to be one of the most important in terms of linking up the various franchises. The introduction of Thor Odinson and Stephen Strange not only makes for some great physical comedy, but it also helps introduce Doctor Strange's main hero (who was relatively insulated during the events of his solo movie) to a character with ties to the overarching Marvel Cinematic Universe. This means that there will be an existing dynamic between these two heroes when they finally meet in Avengers: Infinity War (we already know that Strange will fight alongside the Guardians, so it seems logical to assume that Thor will be there as well), which means we're seeing the future of the MCU take shape.