Sailen: The Lower City dungeon requires players that are level 40 and up to do normal dungeon mode in which there are only level 49-51 mobs. For players that are level 60 can enter the legendary dungeon mode in which there are only all level 60 mobs and the last boss is level 62.
The drops are very good from the first boss Titehelm, it drops an epic warriors helmet that has 900+ armor and it is a very nice addition to a warrior tank/dps(dps- damage per second). The final boss Sailen King Kha-Anata drops a staff with 23 stamina and 23 wisdom and increase healing power by 63 (Dying power staff). It drops some very nice mage shorts epic in fact and with great spell critical and stamina. Sailen: The Lower City dungeon is harder than all the other dungeons, and it is recommended going with a pro player. Also it’s recommended to wear your best armor.
6/6 tank 2 6/6 mages and a 6/6 monk.
You can find here Sailen Guide.