クロノ・クロス
In "Chrono Cross", Crono, Marle, and Lucca make appearances as ghost children. Kato stated that Crono and Marle's fate "is not thoroughly explained in "Chrono Cross"" but that the two were likely involved in "some kind of incident" related to the invasion of their kingdom by the Porre army. He further explained that an intervention "from outside the original flow of history" had helped Porre build its military, though the details were left out of "Chrono Cross" as they did not directly relate to the sequel.