Spider-Man calls Electro “Sparkles” in The Amazing Spider-Man 2. The nickname is one of Peter Parker’s sarcastic jokes during his encounters with Max Dillon, the electrically powered villain played by Jamie Foxx.
Before becoming Electro, Max Dillon works at Oscorp and is socially isolated, while also admiring Spider-Man. A laboratory accident involving genetically modified electric eels transforms him into a living source of electricity. As his powers grow, he adopts the name Electro and develops a grudge against Spider-Man.
Peter’s “Sparkles” nickname mocks Electro’s glowing, crackling appearance and keeps the hero’s familiar wisecracking style alive even during a dangerous confrontation. In another exchange, Spider-Man responds to Electro’s grand claim that he will be like a god by asking, “A god named Sparkles?”
The nickname is not Electro’s official supervillain identity. His name is Electro, and his civilian identity in this film is Max Dillon. “Sparkles” is simply Spider-Man’s teasing label, making it a canonical answer to the movie-trivia question rather than an alternate character name.