Game Development Reference
In-Depth Information
The opposite case is a static engine that infrequently produces many resources. This
can cause the game economy to shift from periods of scarcity to periods of abun-
dance. In
Caesar III
, the arrival of trade caravans from neighboring cities can have
this effect.
n
Escalating complexity.
The
escalating complexity
pattern depends on a transi-
tion between two gameplay phases. As long as the player can keep up with the rate
at which complexity is created, everything seems under control, but as soon as the
pace passes a certain threshold, the positive feedback mechanism will push the
game to a rapid conclusion; it creates a short losing phase in which the player suf-
fers reverses. In
Tetris,
these two phases are easily recognizable. Most of time the
player is in control, but as soon as the blocks start dropping faster than he can field
them, the game shifts to the losing phase. In Tetris, the complexity production
involves a random factor: the type of block that is being produced. This means that
through some luck and extra effort on the part of the player, she can push the game
back from a losing phase to the normal phase.
n
Stopping mechanism/multiple feedback.
When a gameplay phase depends
on a particular action to continue, you can use a
stopping mechanism
to make that
action less effective because it is used more often. This means that the phase can-
not last forever and will cause a shift to a new phase. In
The Seven Cities of Gold,
a
game about exploring (and exploiting) the New World, the player could avoid con-
flict with the Native Americans by using a feature called “Amaze the natives.” This
worked well at first but became less effective over time, and the player soon had to
use other strategies to succeed, a phase shift. The stopping mechanism is normally
quite subtle. In addition, if the effect of the stopping mechanism does not last, the
game might shift back to the earlier gameplay phase. In most cases, any subtle and
slow form of multiple feedback will have a similar effect.
desiGn challenGe
The previous list is not complete or exhaustive. What mechanisms/patterns can you think
of that create gameplay shifts in games like
Caesar III
or
StarCraft II
?
Progression through emergent phases is difficult to control. But by creating mecha-
nisms that are likely to create phase shifts in those systems, you can set up economies
in which you can predict what type of phase progressions might occur. For example,
in
Tetris
you don't know when the game is going to shift to the losing phase, but
because one of the mechanisms that causes this shift (the drop rate of the blocks)
slowly increases, you know that it
will
eventually happen. As you gain experience
and confidence as a designer, you will find that you will become much better at
designing this type of emergent progression and can use it to build engaging systems
that don't depend on scripted events.
