With the ending of the First Skaven Civil War and the entry of Clan Pestilens on the Council of Thirteen, at last would the children of the Horned Rat make their move on the most powerful kingdom of Mankind, the Empire of the Old World. Over several centuries, the Under-Empire recovered, and once more, the armies of Skavendom grew large. With Clan Pestilens' mighty plagues, and the deadly assassins of Clan Eshin at their disposal, the Council felt it was time to finally enact an invasion of the surface.[1a]