You have to find Kahga's secret chest which is located in the same area you first meet Kahga. From that chest you get location where to go to get evidence of Kahga's treachery. My favorite part of the EA is when I get to slaughter Kahga and her fellow shadow druids! I just replay that part over and over again. I just wish it were a little harder. I like fights that have friendly NPCs fighting with you. It would be so cool to have a big hard fight with lots of tough enemies and friendly NPCs.