Priest
Priest is a healer class so by this class you must focus on healing. You can combine that with an Evasion or HP Build.
Main stats to focus on
Critical Rate
Evasion
Max HP
Healing Power
Attack Speed
Magic Attack
Force core to use in slots
Use 'Evasion' force core in every slot item you have.
Example 5 option item stats
Critical Rate
Evasion
Max HP
Healing Power
Attack Speed
Example 4 option accessory stats
Critical Rate
Evasion
Healing Power
Magic Attack
Runes to use [not released in the US version]
Healing Power [x5]
Magic Attack [x5]
Max HP [x5]
Evasion [x5]