It's learned rapper Coolio almost played Scarecrow in a sequel to the 1997 Batman & Robin movie.
The Graphics Burleson Star posted an interview with Coolio in which he states: "The only reason I did that part was because they promised me the villain part in the following Batman, which they didn't do because Joel Schumacher — they fired him. Me and him didn't get along that great anyway. … The next Batman the villain was supposed to be the Scarecrow."
As noted, Coolio did cameo in Batman & Robin in a scene involving Barbara (Alicia Silverstone) where Coolio oversaw a street race.
The sequel to Batman & Robin would have featured Scarecrow teaming up with Harley Quinn, who would have been the daughter to Jack Nicholson's Joker from the 1989 Batman movie, with the plot featuring Batman going mad and being committed to Arkham Asylum. A hallucinating Batman would have had to confront all the villains from the previous movies including cameos from Danny DeVito (The Penguin), Michelle Pfeiffer (Catwoman), Tommy Lee Jones (Two-Face) and Jim Carrey (The Riddler), all leading up to a final confrontation with the return of Jack Nicholson's Joker.
Joel Schumacher also approached Nicholas Cage for the part of Scarecrow.
"After Forever's success, I wanted to do The Dark Knight. It was going to be very dark. I remember going to the set of Face/Off and asking Nic Cage to play the Scarecrow. The studio, and I'm not sure the audience, was in a frame of mind to go too dark with Batman at that time," Schumacher in a previous interview a while back, reports THR.
The sequel to Batman & Robin was eventually scrapped with Christopher Nolan coming on board with Batman Begins and his Dark Knight Trilogy.