Spirit Attacks (also referred to SPs) are powerful attacks that are much like Limit Breaks in the Final Fantasy series. Every character has one, but they get it after achieving a certain level. To use one, the character must have their SP bar full, and Zael must use Command Mode to direct his party members to use them. The SP bar fills as damage is dealt and taken, and increases a lot if an ally loses a life. Yurick and Calista have different SPs during certain points of the game as part of the story. All status boosters/effects are only for a short period of time.
Calista: Her SP is Ancient Barrier. She casts an impenetrable purple barrier that protects and heals Zael from everything as well as repulsing all enemies away. During the boss of Chapter 37, Calista can use Ancient Summon to call the Lazulis Sentinel Mitra to aid her.
Yurick: His SP is Meteor. Prior to the final boss, Yurick can summon falling Meteors to the selected enemies, dealing major damage and also inflict Guard Break. During the final boss fight, Yurick achieves Big Bang which deals a LOT of damage to the boss and also breaks his barrier.
To spread the SPs; Accelerate and Ancient Barrier, Zael must diffuse "himself", so his friends can also gain the effect.