Man Of Steel
For Batman vs Superman and his Justice league universe, Director Zack Snyder decided that he needed an older, battle-hardened Batman. But it was the Superman special effects team who established that Batman was already a pop culture icon. Remember when Zod discovers his heat vision in a battle and causes a skyscraper to fall apart on Superman? Just then on one of the cubicles can be seen a “Keep Calm and Call Batman” sign. He might not have planted the Easter egg himself, but Snyder took the advice to heart!