when an assassin reaches the end of his final year, he must undertake a "final exam" known as 'the run', which consists of an oral test, a run through an obstacle course at night in ankh-morpork and the targeted killing of a single individual. as described in "pyramids", it is designed to test all aspects of the trade, including covert maneuvering, climbing, trap evasion, contingency planning, and (at the end) the ability to actually line up your target and finish the job—all under pressures akin to a real contract (failure is always fatal, and students have bounties on them during 'the run'). to prepare for 'the run', the guild encourages particularly competitive forms of recreation; in particular the "wall game" (far more sadistic than the real-world eton wall game, it is essentially an extreme hybrid of rock-climbing and dodgeball), and stealth chess. furthermore, a school sport is edificeering—the climbing of buildings, often done on unusual/notable buildings in the city itself, with each major building having a rating out of 10 representing how difficult it is to climb (as noted in "pyramids"). school houses have their own teams, and the teams compete against one another. another activity that occurred in later years involved "extra-credit" assignments given to particularly adept pupils, particularly those growing overly confident of their own abilities. these assignments generally required the student to stalk and simulate an attempted assassination on commander of the watch sam vimes, an exercise which was generally both futile and highly educational.