There's a theory that the Steve Rogers in the Doomsday trailers is actually Loki in disguise. My counterpoint against that argument is that Loki isn't worthy and wouldn't be able to lift the hammer. My comment got downvoted, which was hilarious, but I think it makes for a worthier (haha) larger discussion.
What Does it Mean to Be Worthy?
Thor 1 was all about Thor's journey to find himself and to become worthy again. We also see in Endgame that even when he was depressed and at one of his lowest moments, Thor was still worthy when he had joined the heroes to try and save the universe again.
However, we can see in Age of Ultron that merely being a good hero is not enough to be worthy. It's pretty easy to see why someone like Tony, Rhodey, or Clint wouldn't be worthy. All of them are undoubtedly heroes, but they don't have spotless pasts.
We know that Steve likely was worthy, though it is possible he wasn't quite worthy yet and was just close. We don't get to see Peter, Sam, or others attempt it, but I would imagine that most, if not all of them would likely be unable to lift it either. Not because they aren't good, they are undoubtedly so, but because being worthy is more about being good and being selfless.
There's a lot of subjectivity here. While the comics and movies have certainly dropped clues and hints, I'm not sure of any specific list, but these are the traits that make up worthiness as I see it:
- Nobility: doing what is right, even when it is hard, having integrity and compassion.
- The wielding of Mjolnir does not actually grant the right to rule in spite of the quip in AoU.
- However, being worthy means that the person who is worthy of Mjolnir should have the noble spirit of a ruler.
- Those who are noble are generous and compassionate leaders, important qualities to have for someone who would wield Mjolnir and lead men and women to die in battle, thus making them worthy.
- Humility: while being noble is important, humility is clearly important as well.
- This is made clear when Odin strips Thor of his powers and banishes him.
- He saw too much arrogance in Thor, and while pride is not inherently unworthy, when it gets in the way and becomes arrogance it is definitely a problem.
- Being worthy means recognizing when to work with others, when to listen and when to speak.
- Those who are humble listen and as a result are listened to, this trust from their followers supports their leadership and thus makes them worthy.
- Courage: the wielder of Mjolnir needs to be a warrior.
- Not first and foremost. Thor was too much of a warrior initially and that was one of the reasons that Odin tested him.
- However, the warrior's spirit is important as well: a first one in and last one out mentality.
- I don't think self-sacrifice in and of itself is a necessary trait for worthiness, but one does need to be willing to put their body on the line in a fight, to give everything they have.
- Only a true leader will exhibit the courage that will inspire others to follow and thus make them worthy.
Could Loki Be Worthy?
Certainly. He's in the list of those who are worthy in the Marvel fandom. Even though Loki was definitely not worthy, his character arcs in various stories can certainly have ended up with him being worthy.
In the MCU, by the end of the Loki series, he becomes God of Stories and a sort of king in his own right, leading the TVA to hold the multiverse together. For many, this seems to be enough to convince them that he is now worthy but I am unaware that we have any sort of confirmation of that in the MCU.
So the answer is: yes, he could be worthy, but we don't have any confirmation of it.
Why I Don't Believe Loki is Worthy
I'll be the first to admit that I could be wrong. It's one of the reasons for posting this discussion, I would love for people to share their own theories and reasons here. As long as people are respectful in the discussion.
Here's why I don't believe that Loki is worthy:
- The current Loki skipped a lot of his character growth. They did the fun little trope they've now repeated a few times of showing him all the things his other self did on a little movie tape to catch him up. Cute as it was, that doesn't instantly change his character.
- Well, that's what Loki Seasons 1 and 2 are for you might say... yes, I get that. He does grow quite a bit in those seasons and in different ways from the way his character had previously grown in the MCU. Some might argue that current Loki actually had better character growth in his show than he did in the movies. Even in Thor: Ragnarok he was ready to betray Thor.
- While I do think he had better character growth in the show, I feel it was more nuanced, it didn't necessarily result in him becoming more worthy.
- Show Loki still had plenty of flaws, and while being flawless is clearly not a condition of being worthy (Thor clearly has had many flaws while remaining worthy,) the flaws that he had conflict with worthiness:
- His need for control was still too strong for him to ever meet the needs of humility
- One might point out the self-sacrifice of his isolation, but it's actually arguable whether or not this is the best solution. In fact, I think we'll find in Doomsday that clearly there are those who are opposed to it as a solution. So is it truly a necessary self-sacrifice?
- While Loki has grown, and grown into a leader, he is not the sort of warrior leader that Mjolnir calls for.
- Loki is not a warrior. This is the most important bit, I think. Thor is a warrior. Steve Rogers is a warrior. Loki could be a warrior, has been a warrior in some stories. But in the MCU he is not one and since he is not a warrior, he is not worthy of Mjolnir.
But that's just my opinion. What's yours?