Howl, you crazy bastard! If you let forth a rousing yawp, the spirits of the Earth will answer you. Wyrm creatures far beneath the Earth's crust will cause tremors in the ground above them.
Although the terrible quakes cause by this Gift seem awful, they merely reflect the sort of test the Galliard must endure in the Shattered Labyrinth to learn it. The worst scenario is one in which the labyrinth collapses in on itself.

System: The extent of the damage inflicted depends on the amount of Gnosis is channeled into the Galliard's "rousing yawp." One point of Gnosis causes a minor tremor, collapse underground tunnels, knock down trees, or open sinkholes. Five points can cause structural damage to a building, collapsing walls on anyone within several feet of it. In each case, victims should roll Dexterity + Dodge or Dexterity + Athletics to stay on their feet, escape from collapsing buildings, or dive for cover.

Books:
Book of the Wyrm