what exactly is a limit break? is this some sort of anime RPG thing?
A limit break, as it functioned in Final Fantasy 7, is a meter that would fill up as the player took damage, and when it's full, the player could then unleash a powerful attack, sometimes consisting of multiple damaging strikes that would add up to a big amount, the gauge then empties by the end of the attack
When a limit break is used, an aura of a specific color forms and swirls around the player (as seen in the picture in the OP) as a sound of the attack being readied is heard, then the attack commences
For reference,
this is a video of all of the limit breaks in Final Fantasy 7