Spider-Man: No Way Home sees Tom Holland's Spider-Man contending with supervillains from across the multiverse. Trailers have teased the Marvel Cinematic Universe's collision with the realities seen in pre-MCU Spidey films, giving fans a look at returning villains such as Alfred Molina's Doc Ock, Willem Dafoe's Green Goblin and Jamie Foxx's Electro. While Peter Parker will have to handle the presence of these foes in his universe, the classic villains will similarly have to come to terms with the brand new world they have entered. A series of new character posters have offered a better look at the film's villains and Electro, in particular, can be seen making the most of what the MCU has to offer.

As glimpsed in the film's second trailer and various TV spots, Electro is wearing an arc reactor as part of his new MCU costume. This piece of Stark tech has become synonymous with Iron Man, forming the power source for each of the Avenger's armored suits. However, since Electro can generate electricity at will, why is he adopting Tony Stark's power source in No Way Home?

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Electro character poster for Spider-Man: No Way Home

The arc reactor technology was originally introduced to the MCU back in 2008's Iron Man, where it became the power source for both the electromagnet keeping Tony Stark alive and the Iron Man armor. The technology was improved in subsequent films and The Avengers saw the unveiling of Stark Tower -- later Avengers Tower -- which was entirely powered by an arc reactor, making it fully self-sustaining for at least a year. It's easy to see the appeal of a sustainable source of such massive amounts of energy to an electricity-based villain like Electro. However, Electro has been seen generating his own electrical energy. So why is he now using an external power source?

It may be that this version of Electro, as first seen in The Amazing Spider-Man 2, cannot endlessly generate energy. During one of his first scenes after gaining his powers, he is seen grabbing hold of power lines in Times Square, apparently absorbing the electricity within them. Later, when Harry Osborn releases him from captivity, Harry uses a taser on Electro, which seems to give him the power boost he needs to escape his bonds. Along with the fact that he then seeks to claim control of New York's power grid, this all suggests that Electro needs to charge himself by absorbing electricity. If this is the case, the vast amount of energy generated by an arc reactor would make it a terrifying weapon in Electro's hands, potentially making him more powerful than ever before.

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Jamie Foxx's Electro in Spider-Man: No Way Home

Alternatively, Electro's power of electrostatic energy generation may have been affected by his journey across universes. The animated Spider-Man: Into the Spider-Verse showed cross-dimensional travel having a disruptive effect on individuals who were in the wrong universe. While it is not clear if that film and No Way Home are part of the same multiverse, if the villains in No Way Home do experience similar side-effects, Electro may find himself unable to generate electricity outside of his home universe. This could also explain his change in appearance; while he had translucent blue skin through which constant energy pulses could be seen in The Amazing Spider-Man 2, his regular human appearance has been restored in No Way Home. Maybe traversing the multiverse has left Electro able to manipulate but not create electricity, rendering him reliant on an arc reactor.

Whatever the reason for Electro's use of the arc reactor, the amount of power the device can generate is sure to transform Electro into a truly formidable opponent for the MCU's Spider-Man. Alongside Doc Ock's Iron Spider-enhanced tentacles and the Green Goblin's upgraded suit, Electro's arc reactor appears to be one of many ways the MCU's technology is making Spider-Man's classic foes deadlier than ever.

To see Electro enter the MCU, Spider-Man: No Way Home hits theaters on Dec. 17.

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