An instance is a multi-level dungeon embeded within the world - a special quest area.
Up to three characters can enter an instance at the same time - however only one of them (the group leader) can be active. The other two need to set their characters up as mercenaries, pass the group leader their mercenary passwords and wait for the results. Typically you will try and arrange to have one character of each class.
A character can enter an instance up to three times a day (although they can buy additional entries and they occasionally turn up as special rewards). Four times at level 84.
when you reach level 50, you could also challenge instances 20 levels below your level for free (does not cost AP or instance time) once a day.
each instance costs 1 instance time and some action points
Full instance list (current as of May 23, 2011)
|Instance Name||Req. Level||Recomm. Level||Zone||Layers||Instance Gear Reference Page|
|Claymose Altar||27||32||Glancer||2||Claymose Altar Gear|
|BloodAxe Camping Ground||33||38||Glancer||3||BloodAxe Camping Ground Gear|
|Nether Wind Fort||43||47||Thunderclap||4||Nether Wind Fort Gear|
Silent Hill Gear
|Tus Camping Ground||57||60||Pandar Prarie||3||Tus Camping Ground Gear|
|Ancient Stone Statue Group||63||66||Pandar Prarie||3||Ancient Stone Statue Group Gear|
|Cold Wind Grave||67||70||Orcmu||3||Cold Wind Grave Gear|
|Splitpaw Mine||77||80||Orclar||3||Splitpaw Mine Gear|
|Ancient Arena||83||85||Orclar||3||Ancient Arena Gear|
|Sandwalker's Den||87||90||Unliving Desert||3||Sandwalker's Den Gear|
|Flaming Dragonnest||93||95||Unliving Desert||3||Flaming Dragonnest Gear|
|RotTrace Mire||97||100||Crystal Coast||3||RotTrace Mire Gear|
|Mutas Shrine||103||105||Crystal Coast||3||Mutas Shrine Gear|
|Death Cape||107||110||Orcter||3||Death Cape Gear|
|Despair Plain||117||120||Disarn||3||Despair Plain Gear|