To Wake the Leviathan

Publisher's blurb: Across the infinite layers of the Lower Planes, a band of heroes desperately hunts for the whereabouts of an ancient weapon — one that could very well turn the tide of the eternal Blood War. With the help of the archmage Mordenkainen, these adventurers must stop the great Leviathan from falling into fiendish hands. Can they unlock the mysteries of the war machine before it's too late?