The Long-Awaited Reunion
A possible reunion between Thor and Loki is perhaps the most anticipated in the Marvel Cinematic Universe, but some essential plot points would need to be addressed. Loki showrunner Kevin Wright suggested that Loki and Thor will indeed reunite in the MCU's future following the dramatic conclusion to Loki season 2. While this would complete character arcs for both characters, there is a glaring obstacle that would need to be managed.
Chris Hemsworth's Thor and Tom Hiddleston's Loki in the elevator scene in Thor Ragnarok
Tom Hiddleston's Loki was introduced early in the MCU timeline, alongside Chris Hemsworth's Thor in Phase 1's Thor. Hiddleston proved so successful that he remained a key figure throughout the MCU's Infinity Saga. After seemingly dying in Avengers: Infinity War, Loki returned to lead his own series of Disney+, during which the character would develop significantly. This newfound evolution has prompted speculation of Loki reuniting with his brother Thor in the MCU's future, which is seemingly possible.
Thor and Loki at the start of Thor Ragnarok
Thor and Loki's Emotional Journey
It's easy to understand why Thor would have an emotional response to being reunited with Loki. Thor witnessed his version of Loki die at the hands of Thanos in Avengers: Infinity War. After years of falling for Loki's faked deaths, Loki's Infinity War death was very obviously final and particularly brutal. It was also notable for Loki's valiant attempt to stab the Mad Titan, signaling the character's transition from villain to hero. Thor always wanted his brother to become a hero, believing him to be misguided and misunderstood.
Tom Hiddleston as Loki being choked to death by Thanos in Avengers: Infinity War
Learning that Loki has finally assumed a heroic position would provide Thor with substantial closure and complete his character arc regarding Loki's salvation. Loki, on the other hand, would be less emotionally invested in a reunion with the MCU's Thor. Firstly, the surviving Loki depicted in Loki is from a different universe than the MCU's Thor, having left the MCU's Loki timeline just after the Battle of New York in The Avengers. This Loki has not gone through the same compelling character arc as Loki from the MCU's Earth-616.
Odin walks with young Thor and Loki in the MCU
The Significance for Loki
While Earth-616 Thor isn't the one that Loki grew up with, he inadvertently played a crucial role in Loki's life. Thor was not a part of the group that traveled back to 2012 during the Avengers: Endgame time heist, which caused Loki's escape and eventual capture by the TVA. However, Thor was a part of this universe and involved in determining the heroes' plan, and therefore triggered Loki's subsequent narrative in Loki seasons 1 and 2. Loki may inherently care about this universe for its role in shaping his future and development into a hero. Loki might additionally care about the version of Thor who believed that Loki was a misguided hero.
Loki holds the Tesseract in Avengers: Endgame
Thor from Earth-616 believed that Loki had redeemed himself. Reuniting Loki with this Thor would provide far greater emotional depth - with Loki finally becoming the hero that Thor believed he could be. This Thor is more invested in Loki's redemption and, therefore, would be the perfect variant to depict the brothers' arc concluding when Thor and Loki finally reunite in the MCU.
Chris Hemsworth's Thor over Tom Hiddleston's Loki's body in Avengers Infinity War