"Kingdom Hearts 3" was absent during Square-Enix's presentation at E3, reports IGN, and this has been done on purpose in order to give priority to "Kingdom Hearts 2.8 HD: Final Chapter Prologue," a title with three different segments that will prepare gamers for the events and gameplay that will unravel in "Kingdom Hearts 3."

"Final Chapter Prologue" co-director Tai Yasue explained that they want players to quickly leap into the action of "Kingdom Hearts 3" and that "Final Chapter Prologue" will prepare players for that jump by exploring some of the gameplay mechanics and story segments that will be further emphasized in the last game. 

As stated by IGN, the main game in the prologue entry is "Dread Drop Distance," which was originally launched for the Nintendo 3DS. It will focus on the trials Riku and Sora face as they train for the inevitable fight against Xehanort. One such element that the game will introduce is a card system that replaces the touch screen-based mechanics of the 3DS original.

"Birth By Sleep - A Fragmentary Passage" is a much shorter segment that focuses on Aqua, one of the original Keyblade owners and her story will tie into the origins of Xehanort and the truth regarding the nature of the titular Kingdom Hearts.

The final entry, "χ Back Cover," is a cinematic segment that tells the story of the Foretellers. All three segments will tie into the story and gameplay of "Kingdom Hearts 3." They will all complete and further expand the "Dark Seeker" saga of the franchise.

Given that "Final Chapter Prologue" launches for the PS4 during the holidays and it is expected that "Kingdom Hearts 3" may follow in late 2017. As previously reported, the third main entry has not been listed in Square-Enix's fiscal report for the year which means the earliest possible launch date wll still be after April 2017.