Manifestation of the Soul Trophy in Stranger of Paradise: Final Fantasy Origin

This will pop within the first hour of your game. After the initial fight the game drops you in to start off, you'll go through a mini tutorial on the game's combat system & controls. You'll perform your first soul burst during that tutorial.

A soul burst is one of Jack's main abilities; every thing in the game, be it Jack or an enemy, has a break gauge. It essentially acts as a shield where when it breaks, you take increased damage. For enemies, though, once you break through their gauge, a prompt will pop up to press . If you do it, it will instantly kill the enemy and both return some MP to you and slightly increase your max MP bar.