Keystone didn't particularly appreciate a voice in his head prompting him to do things. He'd had voices in his head telling him to do things in the past; it became traumatic almost instantaneously. Most especially when he discovered to whom the voice belonged. But these were issues from days long past. This one seemed different. 

Their situation, at first seeming insurmountable, now had a glimmer of hope in the details. The undead Knight hadn't moved since he jammed his sword into the earth. He'd spoken a bit, but that dark sword still stood partially embedded in the ground. Point one. 

The ranks of the dead weren't without limit. A thinner section of their ranks could be breakable, easily if they had a person capable of channeling divine power to turn them aside. Point two. 

The voice in his head requested help, and for them to withdraw. This might mean a plan that wasn't entirely suicidal. Pride or honor may prevent Raa from withdrawing in the face of an evil undead enemy, demand that it be faced down. That would have to wait for another time; it was hopeful that the Knight could withdraw with honor considering the overwhelming opposition, plus the call for help elsewhere. 

The corpse swarm took down most of Reverin's wards, and the big guy himself made a hole when his army of walking bones parted to let him through. They might not be a match for the undead Knight, but they could easily make a hole elsewhere, provided they could slow their primary antagonist down. 

Keystone listened to the thrum of the ground, the very heartbeat of the earth, and requested a small favor of it: Tighten around the sword, hold it fast. Curl around the shape of the blade and become as stone. Keep it from moving, just for as long as it took clear the ground. Buy them time. It was a rare event for the large man to call upon the earth. Even when he did, it was generally something innocuous and subtle. Obvious would make him a target. Subtle would save their skin. 

As the horde began to advance on their position, the paladin, still partway inside the door, poised to charge. Keystone, eyes never leaving the enemy, addressed Raa in low tones, "Please, I need you to trust me. We have to leave here, someone needs our help. Grab my pack just inside the door, and get ready to break through the same way we came in."

Gathering courage, Keystone breathed the word most lately added to his vocabulary, "Arcos", while both the fighter and paladin charged for a down point in the wards, perpendicular to the position of the monstrous entity with the booming, hollow laugh. 

Raa opened himself to his divine connection, exclaiming with all the piety he could muster, "MAKE A HOLE, GRAVESPAWN!". 

Keystone glanced to his companion quizzically, just prior to growling and colliding his fists against the remaining wall of animated bone.