FUNDAMENTALS OF GAME DESIGN, SECOND EDITION

Victory Conditions

Not all action games have victory conditions because not all games can be won—in some games, the most the player can aspire to is a higher score. The object of Space Invaders is supposedly to save Earth from waves of evil alien invaders, but each wave gets faster and more aggressive until the aliens overwhelm the player. The game is unwinnable. This design is now considered outdated for any but arcade machines. On other types of machines there is no reason to discourage the player from playing for as long as she wants and indeed completing the game.

The victory conditions in simple action games tend to be either crystal clear and known to the player in advance—Banjo needs to rescue his sister in Banjo-Kazooie —or nonexistent, as in the case of Space Invaders. In action games with a storyline, the designers often change the (apparent) victory condition as the game goes on. In Half-Life, for example, the player's first goal is simply to get out of the Black Mesa research complex, but later she discovers that she has to do more things before she can win the game.