As soon as you have chosen you race, you need to decide your classes. The four main classes in Aion Online are the Warrior, Scout, Priest, and Mage. The comprehensive explanation on two of the main classes-Priest and Mage-in Aion Online are in the following. Leather armor can be worn up from level 1 to 10 by Priests who can then wear up to chain armor afterwards. Their primary weapons are maces and staffs. Moreover they are also one of the two classes who are able to use a shield. This grants them the ability to be the second best tanking class in the game, but many players would hardly call them a tank. Their armor and shield are much easier to be survival, solely because Priests is the only class in Aion Online who has the ability of healing, and that paints a large bull's-eye on their chest. This way Priests are regarded as the most useful class in Aion Online because in the game any scenario needs a healer. The priest Sub-classes are designed to mainly tilt the scale either towards healing or damage healing plus supporting. Mages are only allowed to wear cloth armor and their primary weapons are spellbooks and orbs. Although mages are considered to be the most fragile class in the game they are able to deal the most burst damage by a long shot. In the case Mages go out to fight in combat they are able to kill another player if they get lucky hits. Due to this reason Mages are considered fragile. On the one hand, they are fragile, on the other hand they do have their face of being strong. They are able to control crowd, to get away from enemy with a root ability, and to keep distance with a snare ability. However, if they are caught up with by their opponents they are in dange. Mages receive a protective magiuc shield that absorbs damage.

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