I am a LNC/DRG.
I tested the Level One limit break for LNC/DRG, which enable me to summon the "Buster Sword" and did some mid-air "Omni-slash" for a very short period of time.
When people first saw the animation video of the limit break, there were complaints, I tried to understand and I thought such a fan-service was great instead.
But, after I got to test it myself...
It felt like I summoned a legendary weapon, and it was not my character that was out of class/job, instead the weapon guide my character to attack.
This sort of stuff happens in RPGs/stories all the time, it is not the character but the weapons that enable the character power and spells in till it is controlled, but in other cases where the weapon itself moves on its own.
So...yeah.

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