What is the difference between weapon attack and magic attack?

Weapon attack (Abbreviated Att or ATT) affects physical damage from a warrior, thief, archer, or (but not as much) a magician. and magic attack (Abbreviated M Atk or M ATT) affects the magical damage from a magician's skills. M. Atk does not affect damage for skills in any other class. Additionally, weapon attack plays a MAJOR part in calculating damage, especially for Assassins. This causes the overpricing of Work Gloves or other gloves that have been scrolled for Attack.

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