We all know what happened to Silvermoon during the Third War. Arthas came with his hordes of undead, tore the lands apart, ravaged the city and its people and corrupted the Sunwell. Ever wondered what would have happened if he didn't even get close to the city and was pushed back into the Plaguelands? To be fair, probably not. But I wanted to write what I think would have happened!
Whilst Sylvanas, Athrodar and her family were brought back from undeath and rejoined the side of the living, one race of people who were forgotten by the new former Banshee Queen were the Forsaken. Left on their own again and leaderless, they turned to the closest ally still on the side of undeath and chose Nathanos as their leader.