Crazy Personal Headcanons

[Korbei]

The thirteen shards are actually FFI through FFXIII, though not necessarily in order.

I contend that they are in order and here's why: The First (FF1) contains: A Volcano named Mt. Gulg, dwarves, elves, pixies, the Warrior of Light, a subaquatic "palace". Clearly a reference to FF1. Meanwhile, the Thirteenth was bungled and destroyed by arrogance and ineptitude. As Emet-Selch says "In our ignorance, we created a useless void of the thirteenth." A clear repentance.

[RyuDragnier]

I contend that they are in order and here's why: The First (FF1) contains: A Volcano named Mt. Gulg, dwarves, elves, pixies, the Warrior of Light, a subaquatic "palace". Clearly a reference to FF1. Meanwhile, the Thirteenth was bungled and destroyed by arrogance and ineptitude. As Emet-Selch says "In our ignorance, we created a useless void of the thirteenth." A clear repentance.

To add to this, every Calamity matches how the games started in some manner.
1st Calamity (Wind) = FF5, where the journey was started from the loss of the wind
2nd Calamity (Lightning) = FF12, where technology caused the fall of Dalmasca and led to the story's start
3rd Calamity (Fire) = FF2, where the Emperor set fire to the heroes town, starting the journey for revenge.
4th Calamity (Earth) = FF3, where an earthquake opens up a cave leading to the first crystal.
5th Calamity (Ice) = FF6, where the journey starts in the icy region.
6th Calamity (Water) = FF10, where the game starts during a blitzball (underwater sport) match.
7th Calamity (Astral) = FF7, where the game started during the most chaotic and interesting thing you could imagine...an eco-terrorist attack on a facility.

Now look at the possible 8th Calamity of (Umbral). How does FF1 start? With the generic, boring, "Save the princess" quest.

[Vyrerus]

T
Now look at the possible 8th Calamity of (Umbral). How does FF1 start? With the generic, boring, "Save the princess" quest.

With a prophecy and your team being spat out into a clearing in a forest fairly adjacent to a tower castle city. Who then direct you to save their Princess!

[Bright-Flower]

I contend that they are in order and here's why: The First (FF1) contains: A Volcano named Mt. Gulg, dwarves, elves, pixies, the Warrior of Light, a subaquatic "palace". Clearly a reference to FF1. Meanwhile, the Thirteenth was bungled and destroyed by arrogance and ineptitude. As Emet-Selch says "In our ignorance, we created a useless void of the thirteenth." A clear repentance.

There are references sure but there are FF references all throughout the game. I don't think the 'the shards are actually other FF games' fits because they're all reflections of Eorzea. The same base world but with differences from events unfolding differently.