Kingdom Hearts Dream Drop Distance HD
Main article: Kingdom Hearts 3D: Dream Drop Distance
The collection features an HD remaster of 
Dream Drop Distance, which Nomura stated was essentially a full remake of the game, since the original utilized the two screens of the 
Nintendo 3DS.
Kingdom Hearts χ Back Cover
Further information: Kingdom Hearts χ
Kingdom Hearts χ Back Cover, told through HD cinematics, tells a new tale of the Foretellers and reveal new parts of the series' history. Nomura revealed that 
Back Cover would utilize technology being developed for 
Kingdom Hearts III.
Kingdom Hearts 0.2: Birth by Sleep-A Fragmentary Passage
Further information: Kingdom Hearts Birth by Sleep
Kingdom Hearts 0.2: Birth by Sleep–A Fragmentary Passage is a new, short episode taking place after the events of the original 
Birth by Sleep, told from the perspective of Aqua. 
A Fragmentary Passage, which ties into 
Kingdom Hearts III and uses technology from 
III, is set immediately after 
Dream Drop Distance, when 
King Mickey reveals that he has a few secrets to confess, relating to Aqua and her time in the Realm of Darkness. The story then picks up immediately after the secret ending of 
Birth by Sleep Final Mix, and will last about the length of one world from the series.