Appeared Illusion is a Synthesis item that is exclusive to Kingdom Hearts II: Final Mix+. They can be obtained by Synthesis, defeating the Lingering Spirit, or treasure chests in the Cavern of Remembrance. To make it during synthesis, you add a Serenity Crystal while making a Serenity Crystal. You can also obtain by collecting all Rank A materials for the Moogle shops and completing the Puzzle, Edge.