Re Mind - The other tale that unfolded during the climax of KINGDOM HEARTS III.

Determined to rescue Kairi, Sora travels to the Keyblade Graveyard a short time before the final battle was to take place. Lacking a corporeal form, he traces the hearts of the seven guardians of light. Through experiencing their personal battles firsthand, Sora is about to discover truths that he has never before imagined.

About the base game:

The latest entry in the KINGDOM HEARTS series. Having learned that all their struggles thus far were engineered by Master Xehanort in his plot to start another Keyblade War, Sora and his friends continue their search for seven guardians of light capable of standing against the coming darkness. King Mickey and Riku seek out Keyblade veterans from the past, while Sora, Donald, and Goofy begin a new odyssey across Disney worlds to claim the "power of waking."