The level 20 quest is given by roumenus in roumen. you can hand it in when you reach level 20. The reward you get is a 3-day experience booster (120%)

I agree with O-mie. Where are the cool quests for those who were here in OB and lvled beyond 30. OH wait, I know what they gave us. From 40 on, we are forced to lvl in the same place with the same mobs gaining less and less exp per lvl.

Thanks Outspark.