The Arena is a special place where a very unique type of quest will be available for you to embark upon. Unlike in other quests where you must prepare for yourself your own items and equipment, the Arena will give you a preset list of items , and preset gear that you can pick from. Most Arena quests will not have every weapon class available to pick from, so you should probably make sure you’re familiar with a few different weapons if you want to master the Arena!
The Arena doesn’t always allow four people to cooperate, some Arena quests will set the limit at two people working together. Also, the Arena is timed . There is a time limit of 50 minutes, but lower times will allow you to get up to a maximum of S-Rank! There’s no real perks as far as in-game rewards are concerned, but these times are displayed on your Guild Card for everyone to see so lower times means more bragging rights.
Additionally, completing Arena quests will give you a variety of different coins as rewards, which you can use to make some adorable sets of armor if you’re so inclined.