Strike Orb

Strike Orbs are icons that appear during battle that represent your current class and are also the theme color of your class.

When you come into contact with a Strike orb, it will bounce you a tiny bit (some exceptions) and do an affect relative to your current class.

And some classes have multiple Strike orbs that do different effects on the same class, like Priest and Archer.

The image on the right is a Strike Orb for the Wizard class.