The biggest challenges involved giving the characters a new color, which was difficult because in 100 episodes of television where they were constantly changing, they’d been through a lot of colors.
And a lot of the answer came from us looking back to the pilot and tying certain elements of the characters to those roots in the pilot—e.g. Penguin on the pier with Jim—and giving them colors that showed how they changed.
Take all of Barbara’s permutations, or all Penguin’s different changes, and when you assume that he’s still going to be a villain in the finale, then how can you give him a different aspect?