Let me begin with a lengthy article from my friends @ Hardcore Gaming 101. Chrono Trigger *This covers everything you need to know about the timeline adventure. First, yes time is relative to both titles. Second, you can gain allies from various timelines, and sometimes even enemies. Third, the ending depends on every decision you make, and allies aligned with. *note: this fellow gamer/ writers thought do not influence my own however
I have always felt that "cause and effect" were the main theme from the get go. But never as deep as this. To be honest, I have played CT on the SNES, and enjoyed its illustrious storyline that expands at every turn. It does get a bit complicated keeping track of where points A and B meet eventually.
**Ex note: When it comes to Japanese based role playing games, Chrono Trigger redefined what an RPG truly was meant to be, an experience like no other. Plus its meant to be explored, and indulge players in an immerse world beyond the 2D design. This was however back in the 90's, so take it as it is.
What makes XIII (in the current console generation) work is how its motivations work through each characters distinct personality. Of course, we don't get to see Serah's perspective till XIII-2 (and finding out she did see everything through Light's eyes). Changing their fates, Light disappears, Snow goes off on a mission, everyone's left on their own devices. (er wait hit the breaks!) Not your usual FF type of ending (note: some of the CT staff also worked on this 3 part saga in the FF universe).
Is it "Back to the Future"? Hmm I have been wondering how the writing team connects the dots with alternate timelines when paradoxes are fixed. But every outcome does change the pathway of everything that you have and haven't done thus far.
XIII-pt 3 "End of Days"
It cannot be defined any other way, Light faces her rekindled destiny and challenges everything and everyone she became a part of, friend or foe. What many may not realize right away is that fans actually had a bit of influence on the concept of the last story in the 3rd (and final) part of the XIII saga.