The Earthen Oath

This quest is part of the Sons of Hodir quest chain.

Objectives
Thorim, at the Terrace of the Makers, wants you to use the Horn of the Peaks and call on the Earthen to defeat 20 Iron Dwarves and 7 Iron Sentinels.
 * slain (7)
 * slain (20)

Description
For years I neglected my duties, giving into defeat and self-pity.

Not the brave earthen, however. Their oath to protect the Terrace of the Makers with their lives has gone unbroken.

Even now, they fight the corruption of iron with bravery and selflessness, waiting for the moment in which the tides turn.

That moment has arrived. We must rally what remains of the earthen defenders and lead them into a glorious victory. Sound the Horn of the Peaks to call them to your side and take back the Terrace of the Makers.
 * Horn of the Peaks (provided)

Progress
Hail, ! What news do you bring?

Completion
It's a good start. But my brother's forces will not take long to regroup. We must make our victory a decisive one.