I had hoped that his heartbreaking final moments, Loki promises Thor that "The sun will shine on [them] again." Soon after, Thanos kills Loki by crushing his windpipe, with this death being the only one that wasn't a fake-out.
Still, Loki would return three years later in Loki season 1. After getting his hands on the Space Stone during the Avengers' Time Heist, Loki becomes a variant that sets him on a path to becoming a living Temporal Loom responsible for reviving and holding all the timelines of the multiverse. With Loki's previous promise to Thor still ringing in my ears, I'm convinced that this godlike Loki variant will be the one to reunite with his brother in Avengers: Doomsday.
Chris Hemsworth And Tom Hiddleston Are Both Confirmed To Be In Avengers: Doomsday
Their Names Were Revealed Alongside 25 Others
Marvel Studios announced the start of production for Avengers: Doomsday in March, with a live stream that additionally revealed the first wave of confirmed cast for Avengers: Doomsday. Some names were less shocking than others, with the appearance of Anthony Mackie and Robert Downey Jr. being entirely expected stars. Chris Hemsworth, meanwhile, was the first name to appear, while Tom Hiddleston's appears later down the line of cast chairs. Neither name is surprising to see, but they do carry some significant implications.

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Chris Hemsworth was last Loki's MCU arc culminated in him adopting his new, godlike role as the caretaker of the multiverse. Suffice it to say, it would be a big missed opportunity if Avengers: Doomsday doesn't capitalize on both characters starring in the same MCU installment once again, and Marvel may have just hinted that this will occur.
Marvel Just Released A Video Celebrating Thor And Loki's Brotherly Moments
It Suggests A Reunion Is En Route
As if to stoke expectations, Marvel Studios recently posted a "brotherly moments" compilation to its spanning the myriad MCU movies in which they both appear. Accompanying the video is a description that includes Loki's touching final words to his brother, "I assure you, brother, the sun will shine on us again."
It is impossible to ignore the implications of this video and quote so soon after Chris Hemsworth and Tom Hiddleston were confirmed to be starring in Avengers: Doomsday. I'm convinced that this heralds a reunion, though it would be an interesting one given that the Loki variant holding timelines never experienced a relationship with Thor beyond their fraught interactions in The Avengers. Either way, while I have no doubt this reunion will be touching, I don't expect it will be an entirely jovial matter.
I'm Convinced Thor And Loki Will Reunite In Avengers: Doomsday - And One Will Die
It Seems Inevitable That One Or Both Characters Will Die
Marvel's YouTube video comes at an interesting time, as Chris Hemsworth also shared a video of his own paying homage to his time as Thor in the MCU. With this video, Chris Hemsworth shared a heartfelt message reflecting fondly on his tenure. This has led many to believe that Thor will not survive the events of Avengers: Doomsday, with Hemsworth's message being widely interpreted as a farewell message to franchise fans. While I'm not entirely convinced that Thor's MCU career is over, it would make sense for the character to follow Iron Man and make the ultimate sacrifice.
Perhaps the worst-case scenario is that both die and are reunited in Valhalla.
Then again, the same could be said for Loki. Avengers: Doomsday will presumably culminate in Doctor Doom acquiring godlike powers ahead of Avengers: Secret Wars, and one theory suggests that this will put him at odds with Loki. It would be a somewhat tragic return to form for the fan-favorite character who is particularly prone to dying, after all.
Perhaps the worst-case scenario is that both die and are reunited in Valhalla. The Asgardian afterlife certainly looked quite sunny when Jane Foster entered it at the end of Thor: Love and Thunder, lending credence to Loki's assurances to Thor. Whatever the case, I think Marvel is setting Avengers: Doomsday up to be a tearjerker and threatening to kill off two of the MCU's most beloved characters.

Avengers: Doomsday
Cast
- Thor
- Vanessa KirbySue Storm / Invisible Woman
- Johnny Storm / Human Torch
- Ebon Moss-BachrachBen Grimm / The Thing
MCU Movies
Sources: Marvel Studios/YouTube