The Cerebos was the spaceship of Epzo. He used it to compete in the Rally of the Twelve Galaxies.
After Epzo brought the Thirteenth Doctor and Yasmin Khan on board the ship, he found that he hadn't enough fuel to land on Desolation and so jettisoned the back of the ship. However, the speed boost caused the ship to crash onto Desolation's surface. (TV: The Ghost Monument)