If the Twilight Gate is to fall, we need to get Skullcrusher the Mountain out of there!
Before they left, I saw to it that your SI:7 agents took some explosives hidden in a Twilight's Hammer crate. By now, they will have planted them on the steps leading up to the upper portion of the Citadel.
I want you to set the explosives off and then signal us when that monster's out of the way.
That's when we'll attack and finish off the ogre compound!