Massato Kato stated in a Chrono Trigger Ultimania interview that he and Yuji Horii intended for Crono Spoiler:to stay dead after the Ocean Palace scenario. The party would have to then retrieve a version of Crono pre-dating the Millennial Fair to complete the quest, and then return him to his home time, Spoiler:bitter-sweetly knowing he would go on to die at the Ocean Palace. Square deemed this too depressing and had them write the clone plot device to save him.
Contributed by Cavery210