Maintenance for the week of November 18:
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If you turn in a quest, you get Experience. This experience can be scaled to your level, or not, but you always get experience when turning in a completed quest.
Mobs will only give experience if your 5 or less levels over the mobs you have to fight to do the quests. I don't remember if the experience earned is smaller if your say 5 levels over the mob as opposed to 1 or 2 levels over the mobs. This is something they keep changing. Since I tend to get the levels I need as I need to when questing, I don't pay too much attention to the varying amounts.
So, to get the most experience from a quest overall, then try to do them on or near level so the mobs give the most experience.
Enjoy the game, life is what you really want to be worried about.
PakKat "Everything was going well, until I died"
Gary Gravestink "I am glad you died, I needed the help"