Dark Swamp is a maze for players from lv 40 to 55. This is a PvP section, so be prepared for a fight the moment you dock your boat.
For the offical TOP dark swamp guide,
Entering the SwampEdit
First of all: You need to be between lv 40 and 55 to be able to enter the Swamp.
Second: You need to have a ship in Magical Ocean.
The whirlpool leading to the Dark Swamp is located at (2037,2779) in magical ocean. The map will be open every 3 hours and the entrance will open for only 60 minutes. When the entrance to these mazes open, system will make an announcement stating the coordinates of these entrances.
Once you entered the darp swamp map, you need to go to the docking location, which is south east of the position where you entered the map: at location (313,362).
Equipment found in Dark Swamp that is sealed, can be unsealed by the Dark Swamp Researcher in Shaitan City.