Warning: This article contains SPOILERS for Avengers: Endgame.

Following their successful acquisition of the Infinity Stones, the heroes needed an Infinity Gauntlet to hold it all together in Avengers: Endgame. So, Tony Stark/Iron Man (Robert Downey Jr.) created a brand new one. But how exactly was he able to do it considering the resources he had?

Avengers: Endgame began with Thanos (Josh Brolin) revealing he destroyed the Infinity Stones shortly after the snap that wiped out half of life in the universe, forcing the heroes sit on their failure for five years. But hope blossomed after they found another way in collecting the elemental crystals to undo the Decimation. The remaining heroes pulled off what Scott Lang/Ant-Man (Paul Rudd) calls a "time heist" where they used the Quantum Realm to time travel back to key moments in MCU history where they can retrieve the Infinity Stones. Once they've successfully returned to their current timeline with all Stones, they needed a gauntlet of their own so they could reverse the snap. But with no mention of Eitri (Peter Dinklage) and the existence of another metal glove in Nidavellir, the team had to create their own - and that's where Stark came in.

Related: Avengers: Endgame Creates Marvel's Biggest Timeline Challenge Yet (Seriously)

Avengers: Endgame didn't dwell on Stark's process creating another Infinity Gauntlet. Viewers just see him positioning the stones in preparation for their embedding with Hulk (Mark Ruffalo) and Rocket (Bradley Cooper) both beside him. Design-wise, the gauntlet worked like his Iron Man one. It has the ability to adjust size depending on its wearer (a benefit of Stark using nanotech to create the Infinity Gauntlet), hence why it expanded when Bruce Banner decided to step up and offer to do the second snap. Interestingly, the gauntlet held up after the he clicked his fingers. In fact, unlike the one that Eitri made, it didn't fuse to his hand after, and when they removed it from him, it was still intact. This poses a lot of question considering the lengths that the Mad Titan had to go through just to get his own gauntlet.

We learned from Avengers: Infinity War how Thanos went to Nidavellir and blackmailed Eitri into creating "a device capable of harnessing the power of the Stones" for him. He didn't get into specifics about what kind of material he needed, although considering where they were, he seemingly utilized Uru - the metal ore that the Mjolnir and Stormbreaker was constructed from. It's believed to be able to retain energies, particularly magic - sounding like the perfect material to make the gauntlet. Despite its mystical capabilities, it wasn't what Thanos was primarily after in the middle region planet, however; it was Eitri and his skills as a blacksmith. As Thor (Chris Hemsworth) explained, it's the structural design of his creations that makes it special - regardless of the material used or the being who actually make them. "This isn't about your hands. Every weapon you've designed, every axe, hammer, sword, it's all inside your head," he told the Dwarf king.

Having never established that the gauntlet needs to be made from a special type of material to work, not to mention already knowing what the device should look like, Stark was able to recreate the Infinity Gauntlet on Earth. It's unclear at what point Thanos went to Nidavellir to create his own gauntlet, but at most, he only had the Power Stone. Chances are that it was Eitri's only encounter with the elemental crystals, and yet, he was able to create a holding device for all of them. Stark not only had different entanglements with the powerful Stones, but he also spent time studying the Mind Stone in Avengers: Age of Ultron, resulting in the birth of Vision. So, Stark had enough knowledge about them to craft a paraphernalia that can hold them all together in Avengers: Endgame - maybe even better than Eitri did. In any case, it's established in the MCU that "magic's just science we don't understand yet," and with Stark already using extremely high technology like the nanotech for his suits, it's possible that he's figure out a way to mimic Uru's supposed mystical capabilities through science.

More: Avengers: Endgame's Ending & Marvel Movie Future Explained In Detail

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