Opponent's Class Identification
Learning how to find out your opponent's class by the first seconds you enter the arena is just as important as knowing about the classes weakness and strengths, because this way you have time to choose the right strategy against him. Here I will show you some ways you can do that.
Be Observant
The first things you must check on the opponent is his race and if it's a fighter or a magician, this will give you the half way to find out his class, since we can only join the olympiad games with the base class. Once you check this, now you must see what buffs he is using through the animations, some classes from the same race have a few similar buff animations, so it might be tricky at first, but you will get used to it.
About 10 seconds for the fight to start you can asure what is his class by the weapon and clothing set that he will start the fight, for example, if he wears a heavy armor, a sword and a shield, then he is probably a tanker. Picture this, a human fighter enters the arena with a conversion weapon and starts healing you with Sacrifice to low his HP to 30%, then he uses Angelic Icon and equips a heavy armor set, a sword and a shield, then you can assume that he is a Phoenix Knight.
Watch The Olympiad Games
If you have a difficulty to recognize the classes buffs and their characteristics, I suggest you to watch the olympiad games first for a moment and see who is joining, trying to understand their class while you watch, this way you will already know the player's classes when you join the arena and you will get more expertise to recognize the other classes during the preparation time.
You can also do it with another character while you play at the olympiad, and then you watch while you don't get called, this is a very good way to learn about olympiad strategies too.
Monument of Heroes