Today I will introduce to you the "Game of Spies". You can find it on [Events] interface. Once your character reaches level 33 you will unlock this event that can be done twice per day.
Once you accessed the event UI your character will auto-path to the target NPC to claim the quest and then you will be teleported to the destination of the mission. After finding the target NPC, it will give you the instructions and details of the mission. Remember that you can be killed by other players will doing this event; it is recommended to do this mission carefully.
Once the mission is completed, you are able to refresh the rewards to get a higher reward. Aside from that, the player can be sent directly back to the main city. Take note that there will be a 1.5x reward for completing the mission during the Game of Spies. It is recommended to finish the quests during the exploration to get more rewards. The nation exploration time can be seen on the right side of the event UI.
To make it short, completing this event is difficult because of the enemies that you may encounter as you execute the mission. It is also recommended to have an ally to help and protect you while the mission is still in progress.