This section contains spoilers for: Dragon Age: Origins.
The Blightlands are completely devoid of any life except for darkspawn. Most, if not all plant and animal life has been killed or corrupted by the blight. The Imperial Highway is the only describable landmark. By the end of the Fifth Blight the Blightlands have spread over most of south and central Ferelden. The Korcari Wilds and the area surrounding Lothering have been completely devastated. It is unknown how severe the damage is to other parts of the kingdom farther from the source of the blight.
This section contains spoilers for: Dragon Age II.
The Hawke family flees across the Blightlands being pursued by darkspawn. They encounter a veteran of the Battle of Ostagar, Aveline Vallen, and her wounded templar husband Wesley Vallen. The group continue their flight before encountering a large brood of darkspawn and an ogre. One of the Hawke twins is slain by the ogre, and the remaining party would have surely been slaughtered if not for the intervention of the Witch of the Wilds in the form of a high dragon.
Flemeth struck a bargain with the eldest Hawke child, and agreed to shepherd the group safely to Gwaren, after they slew Wesley out of mercy.