The Great Maze (also simply known as the Maze) is an evil location and place in The Keys to the Kingdom series, a demesne that was ruled by the wrathful Sir Thursday. It was the fourth demense that Arthur gained control of as the Rightful Heir. Tile 500/500, one of the four central tiles, is the “master tile” of the Maze, in that no other tile may move its location unless this one is unhindered. Therefore, to fasten it in place (as in the novel Sir Thursday) is to render the Maze immobile. However, the Maze might later rebuild by the New Architect after the horror ends.