Since the series' inception, Final Fantasy has been a key part of Kingdom Hearts' identity, with a variety of characters making appearances throughout the franchise. While Kingdom Hearts 3 moved away from Final Fantasy representation compared to past entries, Kingdom Hearts 4 has the chance to double down on cameos thanks to a resurgence of Final Fantasy in recent years. One of the best ways to revamp the Final Fantasy representation in Kingdom Hearts 4 is to introduce a new secret boss similar to Sephiroth in previous titles.