Japanese gamers have found that the credits for Kingdom Hearts HD 1.5 Remix contains cutscenes from three other games in the series—Kingdom Hearts 2, Birth by Sleep, and coded. The information, reported by several sources in Japan, was confirmed by KHInsider.
The games shown in the credits are, in a way, comparable to those included in Kingdom Hearts HD 1.5 Remix. One numbered game (Kingdom Hearts 2), one relatively important spin-off game (Birth by Sleep) and one less important spin-off game (Coded, although, perhaps like in the case of 358/2 Days, Square will only include cutscenes).
Is this a hint at the contents of a potential Kingdom Hearts 2 HD compilation? W know one is probably on the way.