James Gunn's Superman has been dominating the news cycle as filming is underway in Cleveland, giving fans a good insight into the movie. With the major roles cast like David Corenswet as Superman, Rachel Brosnahan as Lois Lane, and Nicholas Hoult as Lex Luthor, to name a few, almost all of the major roles are set, but fans are also looking forward to plenty of potential cameos of DC characters.