Kingdom Hearts HD II.8 Final Chapter Prologue is the last HD Collection to be released, after I.5 and II.5. It contains an HD Port of Dream Drop Distance, Kingdom Hearts χ Back Cover, and an all new 'episode' title Kingdom Hearts 0.2 Birth by Sleep -A Fragmentary Passage-. The HD Collection was made for the PlayStation 4.
The game was released in Japan on January 12, 2017 and the rest of the world on January 24, 2017. It was later released for the Xbox One worldwide on February 18, 2020.
The game was later released again in a combo pack for North America only as part of Kingdom Hearts: The Story So Far alongside Kingdom Hearts HD 1.5 + 2.5 ReMIX.. A new boxset is currently being planned alongside Kingdom Hearts HD 1.5 + 2.5 ReMix and Kingdom Hearts III as part of Kingdom Hearts All-In-One Package for North America on the PS4 on March 17, 2020 which previously was a digital-exclusive PlayStation Store product.
Other than just serving as the HD Port of Dream Drop Distance, Kingdom Hearts HD 2.8 also has Kingdom Hearts 0.2 Birth by Sleep -A Fragmentary Passage serve as a sequel to Kingdom Hearts: Birth by Sleep which takes place after the Secret Episode from Birth by Sleep Final Mix that covers Aqua's time in the Realm of Darkness and Kingdom Hearts 3D: Dream Drop Distance which will connect with Kingdom Hearts III. The third game Kingdom Hearts χ Back Cover is a 60 minute HD Cinematic of the Kingdom Hearts χ storyline that is told from each of the Foreteller's perspective.
0.2 Birth by Sleep -A Fragmentary Passage- Story
Starting off from where Another Guardian of Light from Dream Drop Distance left off, Mickey and Yen Sid explain to Riku and Kairi how Aqua's journey was connected to how he obtained his current Keyblade, the Keyblade of Darkness, and also how she was involved with him and Riku sealing the Door to Darkness (which took place back in Kingdom Hearts). Afterwards the group (through Sora shows up late after Mickey, Riku, and Kairi had left) are given their assignments for the preparations on the coming war with Xehanort.
PlayStation 4 trophy support for Dream Drop Distance and 0.2 only.
Unlockable PlayStation 4 theme for each title.
Usage of the Unreal Engine 4 graphics for 0.2 and Back Cover which is also planned for Kingdom Hearts III.
Preview of Kingdom Hearts III gameplay in 0.2
Changes to Dream Drop Distance
Remastered in high definition.
Now runs at 60fps.
Reworking the game to fit one screen, requiring some minor overhaul on the control system including:
Reworking original touch screen features by having the full map pulled up by PS4 touch pad, and giving both the Link System and Dream Eater party switch their own Sub-Menus.
Modifying several mini-games
The Balloon Mini-game now uses the PS4 touch pad as a substitute for the 3DS touchscreen.
The Water Barrel Mini-game now functions like a pinball game
The Treasure Googles Mini-game has been replaced with the Candy Goggles Mini-game due to the removal of the the 3DS camera.
Modifying the opening sequence to fit everything on one screen (though only some of the Mickey Mouse animations are used)
Extending the Drop Times.
Having up to three commands from the Command Menu seen on the screen at a time instead of two.
Adding three new Dream Eaters, Catanuki, Tubguin Ace, and Beatalike that were not in the original game.
Replacing two in-game trophies with two brand new ones due to the removal of 3DS-exclusive features.
The game was originally scheduled to be released worldwide in December of 2016, but was pushed back to January 2017, due to development changes, having the game also being released on the Playstation 4 Pro, and to avoid competition in sales on another Square Enix title, Final Fantasy XV following the latter title's delay.
Unlike the previous two HD ReMIX sets where hints of a future release were seen by accessing the credits from the title screen of the game, instead different cutscenes from Dream Drop Distance and the six previous Kingdom Hearts games from the first two HD ReMIX sets are seen for the main credits for the 2.8 HD set.
Nomura explained in an interview why this collection is called 2.8. Any game without Sora in it is counted as a zero, so Kingdom Heart X Back Cover is not counted. So adding 0.2 and 0.1 to 2.5 equals 2.8. The movie at the end of 0.2 is called 2.9, the final chapter prolouge.