The time of troubles is when the gods were made mortal for stealing the tablets of fate (rules for the gods). A few gods died, Mystra, Bhaal, Bane, and I forget the others. But a mortal known as Midnight took Nystra place when Mystra was killed by Helm, And a mortal known as cyric took bane and Myrkuls (spelled wrong) place, no one took bhaals place. thereis alot more to it, i suggest buying the avatar triliogy it is so awesome.
BTW Cyric killed bhaal, badass human fighter/theif
Apof