You have travelled to the Way of Smiths to aid in its defence. Follow Stóthkell's direction and help the Dwarves of Moria make their stand!
Speak to Stóthkell to see what aid you might lend in the defence.
Follow Stóthkell to learn the source of what is shaking the Way of the Smiths.
Help hold the Way of Smiths against Mazog's assault.
With the Orcs driven off, you should speak to Stóthkell to see if there is anything else he would have you do.