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William Ginter Riva is a recurring antagonist in the Marvel Cinematic Universe, serving as a minor antagonist in the 2008 film Iron Man, and later as a supporting antagonist in the 2019 film Spider-Man: Far From Home. He is a former Stark Industries scientist who was allied with Iron Monger and Mysterio.
Riva started out as the head of a team of scientists working for Tony Stark, even developing a new set of Combat Drones for the company.
However, it was not until he was forced by Stane to make a suit for him similar to how Stark made his to defeat several members of the Ten Rings back in Afghanistan. Stane also commented that Stark has made a power source called the Arc Reactor and that he wants Riva to create a miniature version of it as well. However, Riva fearfully stated that he cannot do that because he is not of the same caliber as Stark's, much to Stane's fury. It eventually turns out that Stane betrayed Stark to the Ten Rings in order to take the company for himself and that Riva was involved in it the entire time.
Spider-Man: Far From Home
It was revealed that Giva was supposedly fired by Stark for his allegiance with Stane following the latter's death, and Riva became very embittered by this by vowing to get revenge on Stark for his dismissal. Following the deaths of Stark, Thanos and the Black Order, Riva joined up with a group of former Stark Industries employees led by Quentin Beck, who formulates a plot to stage terrorist attacks around the world so that he can use his special illusion abilities (as Mysterio) to 'foil' those attacks and usurp Stark as the world's greatest hero. As part of the plan, Giva used his combat drones that he previously created to project super-powered entities called the Elementals; even managing and maintaining the attack drones equipped with Mysterio's specialized illusion tech.
When Mysterio discovers that one of the drone is missing a projector, Riva dismissed it as a minor inconvenience, but Beck soon found footage of Michelle Jones (or MJ for short) finding the projector. Knowing that MJ is now aware of the plot and that she is a classmate of Spider-Man, Mysterio threatened to kill Riva if the matter is not resolved, to which Riva fearfully complied by fixing the weaker drone; even agreeing that MJ and the rest of Spider-Man's friends should be killed to cover their tracks.
However, at London, Spider-Man was able to defeat Mysterio, who supposedly died afterwards. Despite Mysterio's supposed defeat, Riva used recordings from the drones to doctor footage and release the altered events to news outlets exposing Spider-Man's true identity and framing him for the attacks. It is unknown what happened to Riva afterwards.