Treasure Chests that previously appeared in random hunting areas in the game world have all changed to Dimensional Treasure Chests. The new kind of chest gives better rewards that scale according to the level of the hunting ground the chest is found in. Dimensional Treasure Chests don’t just open and give you rewards—instead they take you to another dimension where you can participate in a mini-event to earn the rewards.
If you find a Dimensional Treasure Chest, interact it with to summon a Dimensional Door. Note that you can only use a Dimensional Door that made from a chest within appropriate level range of your character. Go through the Dimensional Door to a single player instanced dungeon.
Inside the area are the devil Verdof and many explosive barrels and walking treasure chests. Killing the barrels and treasure chests yields a plethora of regular herbs to heal you and buff you. Interact with Verdof to begin a mini-game. You must accept his challenge or else you will be kicked out of the dungeon (but you can re-enter through the Dimensional Door if it is still open). He summons three Treasure Chests of which you must choose only one. Choose a chest and destroy it to reward the rewards inside!
The Dimensional Door remains open and a character can remain in the special dungeon for no more than 3 minutes. After this time the door closes and you are evicted from the dungeon to your previous hunting area in the regular game world. Once you have completed the mini-game in this instance you cannot get another mini-game instance until the 3-minute expiration timer has ended, and until you find another Dimensional Treasure Chest of your level range to interact with.