the combined weight of objects, rather than the quantity. A principal goal of each episode is to collect all the treasures, many of which are hidden behind puzzles. As treasures are collected or tasks are accomplished, the player's score increases, providing a rough measure of how much of the game has been completed. The player may traverse the game world and solve puzzles in almost any order, although some passageways require problem-solving to get through, and some puzzles require the player to possess something gained from solving a different puzzle. In ZorkIII, unlike in prior episodes, there is a timed component that directly affects the outcome. An earthquake will occur after about 130 moves, opening one passageway and closing another. In each episode, the treasures are needed to reach the conclusion of the game. Plot Zork does not follow a linear storyline. Most of the setting is established through the game's written descriptions of items and locations, as well as manuals in later game releases. Long before the time the game is set in, the Quendor empire, having conquered everywhere above ground, built a massive cave complex to expand. Two hundred years later, the ruler Lord Dimwit Flathead renamed the empire to the Great Underground Empire and spent his reign building massive, largely pointless projects such as an underground dam and the royal museum. A century later, the empire's overspending caused it to collapse, and all the residents left. The abandoned empire is the setting of the three episodes of Zork. Zork I begins with the unnamed player character near a white house in a small, self-contained area; most of the game occurs underground, as do the subsequent episodes. In ZorkII the player learns of the Flatheads, and meets the Wizard of Frobozz, who was once a respected enchanter but was exiled by Lord Dimwit Flathead when his powers began to fade. The wizard appears randomly throughout the game and casts spells that begin with the letter "F" on the player. These have several effects, such as "Fluoresce", which causes the player to glow, and "Freeze", which keeps the player stuck in place for a few turns. In ZorkIII the player character gathers the garb of the Dungeon Master to become his successor. Once the player has all the items, they must feed an elderly man, who reveals himself as the Dungeon Master and shows them the doorway leading to