What Final Fantasy Games are on the Same Universe?

[EfficientNinja]

13 and 15 might be on the same planet. 15 is originally titled 13 versus. I wont mind seeing a Noctis vs Lightning game someday.

I don't think 13 and 15 are related. The only reason Final Fantasy XV was previously named Final Fantasy XIII was that it was supposed to release after 12. It was only in the order of their release and I can't see any connection on their universes/planets while playing them.

Noctis' game was supposed to release as XIII but they delayed or canceled it at that time. That's why Lightning's game released first and was named Final Fantasy XIII.

 

[Sharon]

VII and X are indeed from the same reality because there is a Shinra poster in Final Fantasy X-2. I believe X is the prequel of VII since Shinra is not yet destroyed in X-2. Both games though are not set in the same planet. Shinra is a multi-quadrillion company that is widespread around that Universe. They are mining on different plants around that solar system. I think the planet in VII is very polluted because they sell energy to richer planets.