Basically, you can select 2 people to team up with or click auto queue, this will team you up with random people from your server around your power level,

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You and 2 other members team up together and fight waves of monsters then finally a boss.

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when a new difficulty is unlocked you can sweep it for 3 days, afterwards a new difficulty is unlocked, After 3 days you can't sweep it, then you can sweep it.

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If you do this dungeon with a friend and you have no keys, no rewards will be given to yourself.

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Level Cap: 30

Rewards; Relic Shards (Increases With Difficulty)