A recent interviewed with Zack Synder about Batman V Superman revealed that the film almost had two of DC’s most well known villains in the it.
Director Zack Snyder said “the Joker and The Riddler both came close to being in this movie.” He continued, “We talked about the possibility of putting them in. [Screenwriter] Chris Terrio and I talked about it a lot and felt that their mythological presence is felt in the movie, and that’s cool, but I didn’t want to get my eye too far off the ball because I needed to spend the time, frankly, with Batman and Superman to understand the conflict.
Instead, Lex Luther and Doomsday were chosen and Wonder Woman also added in. David Ayer took advantage of The Joker not being in Batman V Superman and put him in Suicide Squad.
There will be teases of a Robin costume in the Batcave.
You can extrapolate that if Batman kept his suit like that, it’s a reminder,” Geoff Johns, chief creative officer for DC Entertainment, told EW. “He’s displayed the suit of a fallen ally, fallen friend in the center of the Batcave. It’s right there for a reason, and part of it is to fuel him to continue to do what he does.