Earthshaker was a giant hammer created by Proteus during the age of legends, possibly intended to harness or heighten the strength of Phaestus. The hammer's walnut-wood shaft shimmered with minute symbols of unknown origin. The grey stone hammerhead itself was absurdly large and streaked with ribbons of black mineral. When taken in hand, the leaden implement could be used by adventurers to pound the ground, sending a shockwave which knocked everyone even in surrounding rooms prone off their feet.
While the world reeled from the catastrophe of his assault on the Garden of the Gods and Yggdrasil in 922, Pazuzu took up the God-forged relic to smash the Divine-wrought stone which encased Khalas, freeing the Wanderer from millennia of imprisonment. The effort likewise shattered Earthshaker, leaving only a ruined pile of rubble at the centre of Tomacula, a reminder of demonic defiance against Logosian decree.