Francis Klum he real, superpowered enhanced, Mysterio. He comes from another universe where Spiderman turned evil and he teamed up with the avengers to stop him. (He's thought to be a hero, but has villainous tendencies)

Try to impersonate Scarecrow from Batman Arkham Knight (If specials effects is needed then you may use it, but its preferred to hear your un-altered voice, and we add effects post production)