If you are a low level, do not enter Darkness Falls. It is recommended that your character be at least level 25 before entering Darkness Falls. The colors for levels in Darkness Falls is as follows.

Level 1 through 15: All purple
Level 16 through 20: Some red and a lot purple
Level 21 through 25: Some red and some purple
Level 26 through 30: A little Orange and some red and purple
Level 31 through 35: A few orange and some red and purple
Level 36 through 40: Some blue, less orange, red, and purple
Level 41 through 45: Some gray and blue
Level 46 through 49: A lot gray and a few blue

In level 15 there are yellows. If you look, there are yellows for every level in Darkness Falls from level 15 and above. Darkness Falls is one of the best places to hunt from level 15 and above, besides some select places where nice items drop.