The dungeons are a type instance or arena where you can team up with other players to get rewards when you kill difficult bosses and monsters. Right now you bring your own equipment to clear Dungeons.

Dungeon 1

Bosses: Lesser Shadow, Shadow Guard, Shadow Master, Ascended Shadow.
Difficulty: To complete the dungeon, a maximum of 5 players with good equipment is recommended. Gold apples and shields may be needed. Because the bosses hurt very much it is recommended to use Kings-gear that doesn't take any durability damage.

Is also available with an easier version now, max 4 player!

 

Raid 1

Bosses: Bridge Guardian, Bridge Vex, Bridge Guard, Master Scyer.
Difficulty: To complete the raid 8 players with good equipment is recommended. The final boss (Master Scyer) regen its HP when it is out of combat, so try to always stay in combat. There is no player limit for raids, but the bosses are very difficult .

 

Raid 2

Bosses: Medusa
Difficulty: To complete the raid 6-8 players with good equipment is recommended.
Drops: $5000, 1000 exp, Mythical (50% chance), Shadow (10% chance), Artifact (5% chance)