He utilizes them by empowering his allies or dealing immobilizing attacks against his opponents. In addition to this, these spells can weaken Light resistances of enemies—making a party made purely out of Clerics a viable choice.
At later levels, with their improved healing, defenses and buffs will become one of the most indispensable members of any party. The superior defense and vitality of Clerics make them sturdy adventurers that can take on dungeons that might prove a challenge to other classes.
Clerics can either become Priests, who focus on healing and augmenting allies' abilities and Light-based offensive spells, or Paladins, who specialize in protection and close-ranged combat of the Light element as well. [Source: wikia]
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