A Grave Quake is a ritual performed by the Lich Lords that causes an entire area to shudder and shake, spewing forth zombies and skeletons from the remains in the soil. A single piece of matter is all that is needed, it will knit together everything that it can to provide animations for the effect. The ground then vomits up the animations to attack their enemies. The grave soil spews clouds of flies, writing masses of maggots, and all manner of foul vapors and slime that are inimical to the living.
The very first one was used to help assemble the Bone Plague Army for the Battle of Sunsplint Fields.
Screams shatter the peace of the area as you are moving through it. You tumble to the ground bucking and shifting under you. The minor tremors you have felt over the last several minutes seem to have gotten much stronger. The worst of it subsides slowly. The ground vibrates without pause for nearly a full minute after the initial violent shock. Suddenly, the ground erupts, mud covered white bones crawling from wounds in the earth like open graves! The soil vomits up skeletons of multiple humanoids and creatures big and small alike.
This feature is part of Lich Lord’s Anger Manifest.