Arkadia Instances are special places where players can enter (usually a Key or other form of payment is required) for a specific activity. These Instances have a set timer so that a player must complete the tasks before the time ends, including receiving the reward. In some cases, a Team must be formed before one can enter the Instance but it is possible to create a Team with only one member.
Several mobs are only to found in some of the Instances and are not available anywhere else; also, some loots are only available when completing an Instance (for example Arkoins).
These Vaults are located in the Arkadia Underground; they are named so because they were created by the last surviving Arkadia Knight Sal'diresh when he realized that Arkadian people will be wiped out by the Oratan. He built the Vaults in order to hide whatever was left from the great Arkadian treasures and knowledge.
There are 10 Vaults in total; while located in different areas, they all have the same layout. The difficulty raises from 1 to 10, with higher Mobs and higher costs but with higher reward as well. Once inside a Vault, one has to move from room to room and kill all mobs present; once a room was cleared, the door/gate to the next one opens.
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