In the heart of the Old Forest, a fell sword calls forth evil spirits from the Barrow-downs. Only by destroying the sword can you stop the wood-trolls' blight from spreading and end the forest's misery.
The wood-trolls are corrupting the forest.
You should defeat their leader, Gulmúk Dampmould.
Though the wood-trolls have lost their leader, fell spirits continue to flock to the Old Forest.
You should destroy the sword that has been summoning the spirits.