Bumageddon: The Final Pongflict (retitled Butt Wars: The Final Conflict in the U.S.) is the final book in Andy Griffiths' Bum trilogy, following The Day My Bum Went Psycho and Zombie Bums from Uranus. The book details the events of a young boy called Zack and his adventures to finish the bums once and for all. Plot Immediately after the events of the previous story, Zack Freeman and the entire chapel are crushed under a giant brown blob. He manages to escape with his bum and Eleanor, but the others cannot be rescued in time. As they attempt to do so, four Great White Bums descend from the sky and attempt to crush the protagonists under more giant brown blobs, but are saved, and believed to be burned to death by, another Great White Bum. The group discovers that they have been teleported inside a spacecraft disguised as a Great White Bum named Robobum, which was constructed and is being operated by Ned Smelly. Ned reveals that he had no idea that the zombie bumvasion has happened, as he had been trapped underground in a giant stinkant cave in search for their juice, a rare and sought-after fuel for his spacecraft. After discovering a massive reservoir of the juice and mapping out the cave, Ned had discovered three skeletons huddled under a warning written on the cave wall. One of the skeletons was holding a piece of soap that Zack realizes belonged to his grandmother (who had been sucked into a brown hole along with the Forker, the Flicker, the Great White Bum and his cronies, the Prince and Maurice). The warning foretold to future readers that Great White Bum was using the brown hole to send prehistoric bumosaurs to the future in order to bring along Bumageddon. The group realizes that they can prevent Bumageddon by killing the Great White Bum with the arseteroid that killed the bumosaurs. The group use Robobum to travel back sixty-five million years, but accidentally travel back six hundred and fifty million years due to an error in Robobum's system. There, they realize that they have landed at the exact moment that the Great White Bum hatched from its egg, and Zack attempts to kill it, believing that he will stop Bumageddon by doing so. The Great White Bum escapes and is pursued by the group in Robobum, where Zack inadvertently fixes the time-travel