Combining the keystone will require Norgannon's Binding - a device located in the Engine of the Makers, the large pit beside us. Brann should be down there with the other half of the keystone now. I have instructed him on the use of the device. He awaits your presence.
I will do what I can to keep the iron dwarves occupied, but I do not have confidence that I will hold them for long. King Stormheart is returning to the defense of Frosthold with some of his men shortly. Please hurry, <race>.