Kingdom Hearts HD II.8 Final Chapter Prologue & Kingdom Hearts II.9

Director: Tetsuya Nomura (Kingdom Hearts, Final Fantasy VII Remake)

Announced by Square Enix at the Sony Computer Entertainment Japan Asia Press Conference, the new installment in the series will feature a compilation of three Kingdom Hearts titles for the PS4

• Kingdom Hearts: Dream Drop Distance HD
• No new plot elements to be added.
• Kingdom Hearts X: Back Cover
• Features the "oldest story" in the Kingdom Hearts lore.
• Kingdom Hearts 0.2: Birth By Sleep - a fragmentary passage - 
• Kingdom Hearts III technology is being used to create part of this game, hence the release of KH II.8 on the PS4 and not on say, the New 3DS, etc.
• Nomura stated in an interview with Famitsu that Kingdom Hearts 0.2 would be a mix of Kingdom Hearts III and the original Birth by Sleep game for the PSP. 
• The story of the Kingdom Hearts 0.2 game takes place immediately after Aqua finds Cinderella's Castle in Kingdom Hearts: Birth by Sleep Final Mix. 

Japan release is expected in 2016.

Kingdom Hearts III, which uses Unreal Engine4 technology, will be released on the PS4 and the Xbox 1. Confirmed worlds for Kingdom Hearts III include Tangled and Big Hero 6.

Reference Links:

KH II.8

Nomura Interview