Unpredictable quakes

An earthquake begins automatically near the player and may create one or several large sinkholes. The event does not wait for a command or a special item, so even familiar territory can suddenly become dangerous.
Terrain destruction

The damage affects the land itself rather than only nearby creatures. Buildings, roads and natural terrain may all be caught when the ground splits.
Sound
Custom sound effects accompany the shaking and help signal that an event has begun before the full damage becomes visible.