[Shadow of Udûn]

I felt that mordor's darkness and decay had a lot to do with it's inhabitants and Sauron himself. I always thought that Mordor would eventually (over hundreds of years) clear up, and trees would grow once more, grass would grow, people would live there. Then again, there would still be a lot of orcs in mordor, the remnants of the dark lords armies, so maybe you wouldn't want to live there.