Olympiad Class Battle Certificate
A certificate that proves participation in five Olympiad class battle matches. Take it to the Olympiad Manager. If you also bring Olympiad All-Class Battle Certificate and Olympiad Team Event Certificate, you will get a large reward.
Not dropped by monsters.
Cannot be spoiled.
The chances are official (x1). On servers with x10, x100 and higher rates, drop and spoil come more often.