Gameplay - Fundamentals of Game Design - page 259

at her own pace (as in a turn-based game), then they're not really different from
sequential challenges, but if she has to surmount them all in a limited amount of
time, then adding simultaneous challenges makes the game more stressful. (Stress
is discussed in the next section, “Skill, Stress, and Absolute Difficulty.”)
COUSINS'S HIERARCHY
Ben Cousins, in an article for Develop magazine, suggested thinking of gameplay as a
hierarchy (Cousins, 2004). This topic adopts his idea but modifies it somewhat and uses
different terminology. Cousins referred, for example, to atoms of interaction rather than
atomic challenges .
Cousins studied the game Super Mario Sunshine by making a video recording of the
screen while he played, then examining the results in a video editor, which enabled him
to identify the atoms of interaction in the game. By thinking about what he was trying to
accomplish at each moment as he played, he found that he could organize the gameplay
into a five-level hierarchy with “Complete the whole game” as the topmost interaction,
“Complete the current game level” as the second level of the hierarchy, and so on down
to individual atoms of interaction at the bottom level.
Cousins studied an action game; action games typically require players to use specific
low-level actions to meet low-level challenges (to get across the chasm, jump). In other
genres, however, there isn't a one-to-one mapping between challenges and actions even
at the atomic level. Some challenges may be overcome by several different kinds of
actions; overcoming others requires complex sequences of actions. Accordingly, actions
don't appear in the hierarchy, only challenges.
You should try Cousins's technique of analyzing the way that games organize their game-
play by examining them second by second in a video editor; it's a valuable technique for
understanding gameplay.
An early and still common way of creating simultaneous atomic challenges, typical
of side-scrolling shooter games, consisted of bombarding the player with enemies.
Each enemy represents a significant risk, and the player must defeat each one while
fending off the others. A player who works quickly can generally defeat these added
enemies one at a time while keeping the others at bay.
Other games present more complex and interrelated simultaneous challenges. In its
default mode, SimCity imposes no victory condition; its highest-level challenge is to
achieve economic growth so the player can expand his city. (Expanding the city
itself isn't a challenge, just a series of choices available so long as the player brings
in enough money to keep going.) The player doesn't attain economic growth unless
he can provide a balanced supply of services to the city. The city needs police pro-
tection and power and hospitals and water and so on, all at the same time; each
represents an atomic challenge, and the player must meet all of