Avengers: Endgame suggests that Vision may not truly be worthy. The android famously lifted Thor's hammer in Avengers: Age of Ultron, making him the first non-Asgardian to do so in the MCU. Captain America joined those ranks in Endgame, but his use of Mjolnir was a little different.
In practice, the MCU's rules of worthiness are the same as they've always been in the comics: Odin's inscription states "Whosoever holds this hammer, if he be worthy, shall possess the power of Thor." But those powers and Thor's ability to conjure them has evolved; in Thor: Ragnarok, Odin bluntly told Thor, "you're not the God of hammers," and, indeed, Odinson was able to use his abilities after Mjolnir's destruction.
When Captain America lifts Thor's hammer in Avengers: Endgame, he doesn't just gain an incredibly well-balanced weapon; he's also able to conjure lightning through Mjolnir. Essentially, he possesses the power of Thor, an act that proves his worthiness. However, as Reddit user RabidFlamingo points out, Vision used no such powers when taking on Ultron with the hammer; not even a finger sparkle. Could that be because he wasn't truly worthy after all?
Taken at face value, the rules of worthiness certainly don't have to be read as being reliant on lifting Mjolnir. In fact, it's essentially two constraints that aren't mutually exclusive by definition: someone must be holding the hammer and be worthy. In practice, of course, they are always read as being the same thing, but Vision's lack of lightning bolts may well be an example of that not being the case. It is possible that Vision simply didn't know how to summon the power of Thor - he was born yesterday - or that he didn't have enough time with the hammer to hone his skills, but the deepened lore is certainly an intriguing prospect.
This debate doesn't just exist outside of the movies. At the end of Avengers: Age of Ultron, Tony Stark and Steve Rogers dissected the logic of Vision lifting Mjolnir; they suggested that an elevator (and by extension the coathook from Thor: The Dark World) is inanimate and so unworthy, but what does that mean for an artificially created being? Albeit playfully, Marvel's been allowing the question and limits of worthiness to be put to the task, and subsequently allowed it to be altered should the story need it.
Whether or not the android is worthy won't likely be something that the MCU needs to address any time soon. Vision remains dead following Avengers: Endgame, and even when he does inevitably return to star alongside Scarlet Witch in Disney+ show WandaVision, there's unlikely to be a Mjolnir for him to test worthiness on; Captain America returned it to 2013, where Thor stole it from during the Avengers' time travel mission.
Like many logical yet unconfirmed theories - such as Tony Stark's arc reactor powered by the Space Stone - this is unlikely to get a direct acknowledgment. However, the evidence from Avengers: Endgame is hard to ignore, at least from a speculative level.
- Spider-Man: Far From Home (2019) release date: Jul 02, 2019