Game Development Reference
In-Depth Information
DYNAMIC DIFFICULTY ADJUSTMENT
Over the years, game designers have made a number of efforts to create games that
detect the player's level of skill and adapt themselves to change the player's experience
accordingly. Several approaches have been tried:
•
The first-person shooter game
Max Payne
automatically adjusts the strength of
enemies and the amount of aiming assistance provided to the player based on his
performance. The changes work to keep the player's experience at an appropriate
level of difficulty, but they are transparent to the user.
•
Half-Life 2
checks the state of the avatar's health and ammunition when he breaks
open a crate in the game world, and adjusts the contents of the crate accordingly. If he
is healthy and well supplied, he might find little or nothing, but if he is short of one of
these resources, he might find medical kits or spare ammunition.
•
The racing game
Burnout 2: Point of Impact
automatically changes the performance of
computer-controlled drivers to keep them near the player's car regardless of how well or
poorly she does. No matter what the skill level of the player, this approach ensures a
close race.
•
Crash Bandicoot
, an action game, offers the player extra shields against attack if he
fails to get through a certain section too many times in a row. Players find this mechanism
rather obvious. Furthermore, rather than being a global system like
Max Payne
's, it had
to be implemented separately for each region of the game where it offered extra shields.
•
Madden NFL 09
gives the player a series of explicit tests in its “Virtual Training
Center,” then adjusts the difficulty of the gameplay in the real game based on his perfor-
mance in the tests.
•
God of War
, another action game, detects when the player is dying frequently and
offers him the chance to play again in a lower difficulty mode. In this case, the game
doesn't adapt its difficulty; it simply offers the player the chance to choose an easier mode.
Some players complain that they find this patronizing; presumably others find it a relief.
DDA systems such as those used in
Max Payne
and
Burnout 2
are the subject of consider-
able debate within the game industry and for the moment remain experiments rather
than standard industry techniques. Some designers believe that no automated system
can accurately predict how hard a player
wants
his experience to be, so they should not
even be tried. In fact, as with everything else in game development, there are tradeoffs.
Good DDA systems are time-consuming to build and tune, but they can significantly
enhance the player's experience if done well.
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