Each spell class has it's own set of special effects that it can cause apart from the damage the spell does. Below is a list of their special effects:
Air: Reduces marksmanship, can cause paralysis, residual damage.
Shadow: Reduces marksmanship, can cause large amounts of residual damage.
Earth: Reduces marksmanship, can cause paralysis, best selection of multi-target attacks.
Fire: Reduces marksmanship, can cause paralysis.
Water: Reduces marksmanship, can cause paralysis, residual damage.
Healing: Multiple healing abilities, can temporarily increase elemental defense.