The Thundercrusher was a sky pirate sky ship which appeared in Cloud Wolf and Clash of the Sky Galleons and participated in battles in both books. The Thundercrusher was outfitted with a massive wrecking-ball which it used to pummel enemy sky ships in close combat. In the Battle of the Great Sky Whale, the Thundercrusher used its wrecking ball to attack the Great Sky Whale's aftcastle, and it fled the battle midway through. In the Battle of the Bringer of Doom, the Thundercrusher came in after the sky pirates' initial attack to pound the league ships into surrender. However, the Thundercrusher was easily destroyed by the Bringer of Doom mere moments after it entered the battle.