The Final Fantasy 14 development team considered adding a battle royale mode to the MMO.
One idea was a battle royale mode featuring only blue mages - the unique job that learns skills and magic by battling enemies.
The mode would take place in a large arena with a gradually shrinking battle area, as is typical of the genre. Players would then use the blue mage learning ability to acquire spells instead of collecting weapons.
However, this idea was dropped. Another idea was to focus solely on eight core jobs, but this was also dropped. One reason is that it was believed players would want to use their own jobs in PvP rather than pre-determined options.
The Crystalline Conflict mode has proven popular with players, despite some awkward balance changes.
And as for Final Fantasy battle royales, there's always the mobile game Final Fantasy 7: The First Soldier.